Stuxnet is a
malicious computer worm
A computer worm is a standalone malware computer program that replicates itself in order to spread to other computers. It often uses a computer network to spread itself, relying on security failures on the target computer to access it. It will ...
first uncovered on June 17, 2010, and thought to have been in development since at least 2005. Stuxnet targets
supervisory control and data acquisition
SCADA (an acronym for supervisory control and data acquisition) is a control system architecture comprising computers, networked data communications and graphical user interfaces for high-level supervision of machines and processes. It also cove ...
(SCADA) systems and is believed to be responsible for causing substantial damage to the
Iran nuclear program.
Although neither the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
nor
Israel
Israel, officially the State of Israel, is a country in West Asia. It Borders of Israel, shares borders with Lebanon to the north, Syria to the north-east, Jordan to the east, Egypt to the south-west, and the Mediterranean Sea to the west. Isr ...
has openly admitted responsibility, multiple independent news organizations claim Stuxnet to be a
cyberweapon
Cyberweapons are commonly defined as malware agents employed for military, paramilitary, or intelligence objectives as part of a cyberattack. This includes computer viruses, trojans, spyware, and worms that can introduce malicious code into ex ...
built jointly by the two countries in a collaborative effort known as
Operation Olympic Games
Operation Olympic Games was an black operation, unacknowledged campaign of sabotage by means of cyber disruption, directed at Iranian Nuclear program of Iran, nuclear facilities by the United States and Israel. As reported, it is one of the first ...
. The program, started during the
Bush administration, was rapidly expanded within the first months of
Barack Obama
Barack Hussein Obama II (born August 4, 1961) is an American politician who was the 44th president of the United States from 2009 to 2017. A member of the Democratic Party, he was the first African American president in American history. O ...
's presidency.
Stuxnet specifically targets
programmable logic controller
A programmable logic controller (PLC) or programmable controller is an industrial computer that has been ruggedized and adapted for the control of manufacturing processes, such as assembly lines, machines, robotic devices, or any activity that ...
s (PLCs), which allow the automation of electromechanical processes such as those used to control machinery and industrial processes including
gas centrifuge
A gas centrifuge is a device that performs isotope separation of gases. A centrifuge relies on the principles of centrifugal force accelerating molecules so that particles of different masses are physically separated in a gradient along the radiu ...
s for separating nuclear material. Exploiting four
zero-day flaws in the systems, Stuxnet functions by targeting machines using the
Microsoft Windows
Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...
operating system and networks, then seeking out
Siemens
Siemens AG ( ) is a German multinational technology conglomerate. It is focused on industrial automation, building automation, rail transport and health technology. Siemens is the largest engineering company in Europe, and holds the positi ...
Step7 software. Stuxnet reportedly compromised Iranian PLCs, collecting information on industrial systems and causing the fast-spinning centrifuges to tear themselves apart.
Stuxnet's design and architecture are not domain-specific and it could be tailored as a platform for attacking modern SCADA and PLC systems (e.g., in factory assembly lines or power plants), most of which are in Europe,
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
and the United States. Stuxnet reportedly destroyed almost one-fifth of Iran's
nuclear centrifuges. Targeting industrial control systems, the worm infected over 200,000 computers and caused 1,000 machines to physically degrade.
Stuxnet has three modules: a
worm
Worms are many different distantly related bilateria, bilateral animals that typically have a long cylindrical tube-like body, no limb (anatomy), limbs, and usually no eyes.
Worms vary in size from microscopic to over in length for marine ...
that executes all routines related to the main
payload of the attack, a
link file that automatically executes the propagated copies of the worm and a
rootkit
A rootkit is a collection of computer software, typically malicious, designed to enable access to a computer or an area of its software that is not otherwise allowed (for example, to an unauthorized user) and often masks its existence or the exist ...
component responsible for hiding all malicious files and processes to prevent detection of Stuxnet. It is typically introduced to the target environment via an infected
USB flash drive
A flash drive (also thumb drive, memory stick, and pen drive/pendrive) is a data storage device that includes flash memory with an integrated USB interface. A typical USB drive is removable, rewritable, and smaller than an optical disc, and u ...
, thus crossing any
air gap. The worm then propagates across the network, scanning for
Siemens Step7 software on computers controlling a PLC. In the absence of either criterion, Stuxnet becomes dormant inside the computer. If both the conditions are fulfilled, Stuxnet introduces the infected rootkit onto the PLC and Step7 software, modifying the code and giving unexpected commands to the PLC while returning a loop of normal operation system values back to the users.
Discovery
Stuxnet, discovered by Sergey Ulasen from a Belarusian antivirus company
VirusBlokAda, initially spread via Microsoft Windows, and targeted Siemens
industrial control system
An industrial control system (ICS) is an electronic control system and associated instrumentation used for industrial process control. Control systems can range in size from a few modular panel-mounted controllers to large interconnected and in ...
s. While it is not the first time that hackers have targeted industrial systems,
nor the first publicly known intentional act of
cyberwarfare
Cyberwarfare is the use of cyberattack, cyber attacks against an enemy State (polity), state, causing comparable harm to actual warfare and/or disrupting vital computer systems. Some intended outcomes could be espionage, sabotage, propaganda, ...
to be implemented, it is the first discovered
malware
Malware (a portmanteau of ''malicious software'')Tahir, R. (2018)A study on malware and malware detection techniques . ''International Journal of Education and Management Engineering'', ''8''(2), 20. is any software intentionally designed to caus ...
that spies on and subverts industrial systems,
and the first to include a
programmable logic controller
A programmable logic controller (PLC) or programmable controller is an industrial computer that has been ruggedized and adapted for the control of manufacturing processes, such as assembly lines, machines, robotic devices, or any activity that ...
(PLC)
rootkit
A rootkit is a collection of computer software, typically malicious, designed to enable access to a computer or an area of its software that is not otherwise allowed (for example, to an unauthorized user) and often masks its existence or the exist ...
.
The worm initially spreads indiscriminately, but includes a highly specialized malware payload that is designed to target only Siemens
supervisory control and data acquisition
SCADA (an acronym for supervisory control and data acquisition) is a control system architecture comprising computers, networked data communications and graphical user interfaces for high-level supervision of machines and processes. It also cove ...
(SCADA) systems that are configured to control and monitor specific industrial processes.
Stuxnet infects PLCs by subverting the
Step-7 software application that is used to reprogram these devices.
Different variants of Stuxnet targeted five Iranian organizations, with the probable target widely suspected to be
uranium enrichment
Enriched uranium is a type of uranium in which the percent composition of uranium-235 (written 235U) has been increased through the process of isotope separation. Naturally occurring uranium is composed of three major isotopes: uranium-238 (23 ...
infrastructure in
Iran
Iran, officially the Islamic Republic of Iran (IRI) and also known as Persia, is a country in West Asia. It borders Iraq to the west, Turkey, Azerbaijan, and Armenia to the northwest, the Caspian Sea to the north, Turkmenistan to the nort ...
;
Symantec noted in August 2010 that 60 percent of the infected computers worldwide were in Iran. Siemens stated that the worm caused no damage to its customers,
but the Iran nuclear program, which uses
embargoed Siemens equipment procured secretly, was damaged by Stuxnet.
Kaspersky Lab
Kaspersky Lab (; ) is a Russian multinational cybersecurity and anti-virus provider headquartered in Moscow, Russia, and operated by a holding company in the United Kingdom. It was founded in 1997 by Eugene Kaspersky, Natalya Kaspersky a ...
concluded that the sophisticated attack could only have been conducted "with
nation-state
A nation state, or nation-state, is a political entity in which the state (a centralized political organization ruling over a population within a territory) and the nation (a community based on a common identity) are (broadly or ideally) con ...
support."
F-Secure
F-Secure Corporation is a global cyber security and privacy company, which has its headquarters in Helsinki, Finland.
The company has offices in Denmark, Finland, France, Germany, India, Italy, Japan, Malaysia, Netherlands, Norway, Poland, Swed ...
's chief researcher
Mikko Hyppönen, when asked if possible nation-state support were involved, agreed: "That's what it would look like, yes."
In May 2011, the
PBS
The Public Broadcasting Service (PBS) is an American public broadcaster and non-commercial, free-to-air television network based in Arlington, Virginia. PBS is a publicly funded nonprofit organization and the most prominent provider of educat ...
program ''
Need To Know
The term "need to know" (alternatively spelled need-to-know), when used by governments and other organizations (particularly those related to military or intelligence), describes the restriction of data which is considered very confidential and ...
'' cited a statement by
Gary Samore, White House Coordinator for Arms Control and Weapons of Mass Destruction, in which he said, "we're glad they
he Iraniansare having trouble with their centrifuge machine and that we — the U.S. and its allies — are doing everything we can to make sure that we complicate matters for them," offering "winking acknowledgement" of United States involvement in Stuxnet. According to ''
The Daily Telegraph
''The Daily Telegraph'', known online and elsewhere as ''The Telegraph'', is a British daily broadsheet conservative newspaper published in London by Telegraph Media Group and distributed in the United Kingdom and internationally. It was found ...
'', a showreel that was played at a retirement party for the head of the
Israel Defense Forces
The Israel Defense Forces (IDF; , ), alternatively referred to by the Hebrew-language acronym (), is the national military of the State of Israel. It consists of three service branches: the Israeli Ground Forces, the Israeli Air Force, and ...
(IDF),
Gabi Ashkenazi, included references to Stuxnet as one of his operational successes as the IDF chief of staff.
On 1 June 2012, an article in ''
The New York Times
''The New York Times'' (''NYT'') is an American daily newspaper based in New York City. ''The New York Times'' covers domestic, national, and international news, and publishes opinion pieces, investigative reports, and reviews. As one of ...
'' reported that Stuxnet was part of a US and Israeli intelligence operation named ''
Operation Olympic Games
Operation Olympic Games was an black operation, unacknowledged campaign of sabotage by means of cyber disruption, directed at Iranian Nuclear program of Iran, nuclear facilities by the United States and Israel. As reported, it is one of the first ...
'', devised by the
NSA under President
George W. Bush
George Walker Bush (born July 6, 1946) is an American politician and businessman who was the 43rd president of the United States from 2001 to 2009. A member of the Bush family and the Republican Party (United States), Republican Party, he i ...
and executed under President
Barack Obama
Barack Hussein Obama II (born August 4, 1961) is an American politician who was the 44th president of the United States from 2009 to 2017. A member of the Democratic Party, he was the first African American president in American history. O ...
.
On 24 July 2012, an article by Chris Matyszczyk from
CNET reported that the
Atomic Energy Organization of Iran e-mailed
F-Secure
F-Secure Corporation is a global cyber security and privacy company, which has its headquarters in Helsinki, Finland.
The company has offices in Denmark, Finland, France, Germany, India, Italy, Japan, Malaysia, Netherlands, Norway, Poland, Swed ...
's chief research officer
Mikko Hyppönen to report a new instance of malware.
On 25 December 2012, an Iranian semi-official news agency announced there was a cyberattack by Stuxnet, this time on the industries in the southern area of the country. The malware targeted a power plant and some other industries in
Hormozgan province in recent months.
According to
Eugene Kaspersky
Yevgeny Valentinovich Kaspersky (; born 4 October 1965) is a Russian cybersecurity expert and the CEO of Kaspersky Lab, an IT security company with 4,000 employees. He co-founded Kaspersky Lab in 1997 and helped identify instances of government-s ...
, the worm also infected a nuclear power plant in Russia. Kaspersky noted, however, that since the power plant is not connected to the public Internet, the system should remain safe.
History
The worm was first identified by the security company
VirusBlokAda in mid-June 2010.
Journalist
Brian Krebs
Brian Krebs (born 1972) is an American journalist and investigative reporter. He is best known for his coverage of profit-seeking cybercriminals.Perlroth, Nicole.Reporting From the Web's Underbelly. ''The New York Times''. Retrieved February 2 ...
's blog post on 15 July 2010 was the first widely read report on the worm.
The original name given by VirusBlokAda was "Rootkit.Tmphider;" Symantec, however, called it "W32.Temphid," later changing it to "W32.Stuxnet." Its current name is derived from a combination of keywords found in the software (".stub" and "mrxnet.sys"). The timing of the discovery has been attributed to the virus accidentally spreading beyond its intended target due to a programming error introduced in an update. This may have caused the worm to spread to an engineer's computer connected to the centrifuges, further propagating when the engineer later connected to the internet at home.
Kaspersky Lab experts initially estimated that Stuxnet began spreading around March or April 2010, but the first variant of the worm appeared in June 2009.
On 15 July 2010, the day the worm's existence became widely known, a
distributed denial-of-service attack targeted the servers of two leading mailing lists on industrial-systems security. This attack, from an unknown source but possibly related to Stuxnet, disabled one of the lists, interrupting a key information source for power plants and factories. Separately, researchers at
Symantec uncovered a version of the Stuxnet computer virus that was used to attack Iran's nuclear program in November 2007, with evidence indicating it was under development as early as 2005, when Iran was still setting up its
uranium enrichment
Enriched uranium is a type of uranium in which the percent composition of uranium-235 (written 235U) has been increased through the process of isotope separation. Naturally occurring uranium is composed of three major isotopes: uranium-238 (23 ...
facility.
The second variant, with substantial improvements, appeared in March 2010, reportedly due to concerns that Stuxnet was not spreading fast enough. A third variant, with minor improvements, followed in April 2010. The worm contains a component with a build timestamp from 3 February 2010.
On 25 November 2010,
Sky News
Sky News is a British free-to-air television news channel, live stream news network and news organisation. Sky News is distributed via an English-language radio news service, and through online channels. It is owned by Sky Group, a division of ...
in the United Kingdom reported receiving information from an anonymous source at an unidentified
IT security
Computer security (also cybersecurity, digital security, or information technology (IT) security) is a subdiscipline within the field of information security. It consists of the protection of computer software, systems and networks from thr ...
organization claiming that Stuxnet, or a variation of the worm, had been traded on the
black market
A black market is a Secrecy, clandestine Market (economics), market or series of transactions that has some aspect of illegality, or is not compliant with an institutional set of rules. If the rule defines the set of goods and services who ...
.
In 2015,
Kaspersky Lab
Kaspersky Lab (; ) is a Russian multinational cybersecurity and anti-virus provider headquartered in Moscow, Russia, and operated by a holding company in the United Kingdom. It was founded in 1997 by Eugene Kaspersky, Natalya Kaspersky a ...
reported that the
Equation Group
The Equation Group, also known in China as APT-C-40, is a highly sophisticated Threat (computer)#Threat agents or actors, threat actor suspected of being tied to the Tailored Access Operations (TAO) unit of the United States National Security Age ...
had used two of the same zero-day attacks prior to their use in Stuxnet, in another malware called fanny.bmp. Kaspersky Lab noted that "the similar type of usage of both exploits together in different computer worms, at around the same time, indicates that the Equation Group and the Stuxnet developers are either the same or working closely together".
In 2019, ''Chronicle'' researchers Juan Andres Guerrero-Saade and Silas Cutler presented findings indicating that at least four distinct threat actor malware platforms collaborated in developing the different versions of Stuxnet. The collaboration was referred to as 'GOSSIP GIRL', a name derived from a threat group mentioned in classified
CSE slides that included Flame. GOSSIP GIRL is described as a cooperative umbrella encompassing the
Equation Group
The Equation Group, also known in China as APT-C-40, is a highly sophisticated Threat (computer)#Threat agents or actors, threat actor suspected of being tied to the Tailored Access Operations (TAO) unit of the United States National Security Age ...
,
Flame
A flame () is the visible, gaseous part of a fire. It is caused by a highly exothermic chemical reaction made in a thin zone. When flames are hot enough to have ionized gaseous components of sufficient density, they are then considered plasm ...
,
Duqu
Duqu is a collection of computer malware discovered on 1 September 2011, thought by Kaspersky Labs to be related to the Stuxnet worm and to have been created by Unit 8200. The Laboratory of Cryptography and System Security ( CrySyS Lab) of the ...
, and Flowershop (also known as 'Cheshire Cat').
In 2020, researcher Facundo Muñoz presented findings suggesting that Equation Group may have collaborated with Stuxnet developers in 2009 by providing at least one zero-day exploit, and one exploit from 2008 that was actively used by the
Conficker computer worm and Chinese hackers. In 2017, a group of hackers known as
The Shadow Brokers leaked a collection of tools attributed to Equation Group, including new versions of both exploits compiled in 2010. Analysis of the leaked data indicated significant code overlaps, as both Stuxnet's exploits and Equation Group's exploits were developed using a set of libraries called the "Exploit Development Framework", also leaked by
The Shadow Brokers.
Affected countries
A study of the spread of Stuxnet by
Symantec showed that the main affected countries in the early days of the infection were Iran, Indonesia and India:
Iran was reported to have fortified its cyberwar abilities following the Stuxnet attack, and has been suspected of retaliatory attacks against United States banks in
Operation Ababil.
Operation
Unlike most malware, Stuxnet does little harm to computers and networks that do not meet specific configuration requirements; "The attackers took great care to make sure that only their designated targets were hit ... It was a marksman's job." While the worm is promiscuous, it makes itself inert if Siemens software is not found on infected computers, and contains safeguards to prevent each infected computer from spreading the worm to more than three others, and to erase itself on 24 June 2012.
For its targets, Stuxnet contains, among other things, code for a
man-in-the-middle attack
In cryptography and computer security, a man-in-the-middle (MITM) attack, or on-path attack, is a cyberattack where the attacker secretly relays and possibly alters the communications between two parties who believe that they are directly communi ...
that fakes industrial process control sensor signals so an infected system does not shut down due to detected abnormal behavior.
Such complexity is unusual for
malware
Malware (a portmanteau of ''malicious software'')Tahir, R. (2018)A study on malware and malware detection techniques . ''International Journal of Education and Management Engineering'', ''8''(2), 20. is any software intentionally designed to caus ...
. The worm consists of a layered attack against three different systems:
# The
Windows operating system,
# Siemens PCS 7, WinCC and STEP7 industrial software applications that run on Windows and
# One or more Siemens S7 PLCs.
Windows infection
Stuxnet attacked Windows systems using an unprecedented four
zero-day attacks (plus the
CPLINK vulnerability
Vulnerability refers to "the quality or state of being exposed to the possibility of being attacked or harmed, either physically or emotionally." The understanding of social and environmental vulnerability, as a methodological approach, involves ...
and a vulnerability used by the
Conficker worm). It is initially spread using infected removable drives such as
USB flash drive
A flash drive (also thumb drive, memory stick, and pen drive/pendrive) is a data storage device that includes flash memory with an integrated USB interface. A typical USB drive is removable, rewritable, and smaller than an optical disc, and u ...
s,
which contain Windows shortcut files to initiate executable code. The worm then uses other exploits and techniques such as
peer-to-peer
Peer-to-peer (P2P) computing or networking is a distributed application architecture that partitions tasks or workloads between peers. Peers are equally privileged, equipotent participants in the network, forming a peer-to-peer network of Node ...
remote procedure call
In distributed computing, a remote procedure call (RPC) is when a computer program causes a procedure (subroutine) to execute in a different address space (commonly on another computer on a shared computer network), which is written as if it were a ...
(RPC) to infect and update other computers inside private networks that are not directly connected to the Internet.
The number of zero-day exploits used is unusual, as they are highly valued and
malware creators do not typically make use of (and thus simultaneously make visible) four different zero-day exploits in the same worm.
Amongst these exploits were remote code execution on a computer with Printer Sharing enabled, and the LNK/PIF vulnerability, in which file execution is accomplished when an icon is viewed in Windows Explorer, negating the need for user interaction. Stuxnet is unusually large at half a megabyte in size,
and written in several different programming languages (including
C and
C++) which is also irregular for malware.
The Windows component of the malware is promiscuous in that it spreads relatively quickly and indiscriminately.
The malware has both
user mode and kernel mode rootkit
A rootkit is a collection of computer software, typically malicious, designed to enable access to a computer or an area of its software that is not otherwise allowed (for example, to an unauthorized user) and often masks its existence or the exist ...
ability under Windows,
and its
device driver
In the context of an operating system, a device driver is a computer program that operates or controls a particular type of device that is attached to a computer or automaton. A driver provides a software interface to hardware devices, enabli ...
s have been
digitally signed with the private keys of two
public key certificate
In cryptography, a public key certificate, also known as a digital certificate or identity certificate, is an electronic document used to prove the validity of a Key authentication, public key. The certificate includes the public key and informati ...
s that were stolen from separate well-known companies,
JMicron and
Realtek
Realtek Semiconductor Corp. () is a Taiwanese fabless semiconductor company situated in the Hsinchu Science Park, Hsinchu, Taiwan. Realtek was founded in October 1987 and subsequently listed on the Taiwan Stock Exchange in 1998. Realtek has manu ...
, both located at
Hsinchu Science Park
The Hsinchu Science Park (HSP; ) is an industrial park complex that originated as one campus straddled Hsinchu City, Hsinchu County, Chunan and Tongluo, later expanded to cover six campuses across Taiwan. It was established by the government of ...
in Taiwan.
The
driver signing helped it install
kernel mode
In computer science, hierarchical protection domains, often called protection rings, are mechanisms to protect data and functionality from faults (by improving fault tolerance) and malicious behavior (by providing computer security).
Computer ...
rootkit drivers successfully without users being notified, and thus it remained undetected for a relatively long period of time.
Both compromised certificates have been
revoked by
Verisign
Verisign, Inc. is an American company based in Reston, Virginia, that operates a diverse array of network infrastructure, including two of the Internet's thirteen root nameservers, the authoritative registry for the , , and generic top-level d ...
.
Two websites in Denmark and Malaysia were configured as
command and control servers for the malware, allowing it to be updated, and for
industrial espionage
Industrial espionage, also known as economic espionage, corporate spying, or corporate espionage, is a form of espionage conducted for commercial purposes instead of purely national security.
While political espionage is conducted or orchestrat ...
to be conducted by uploading information. Both of these
domain name
In the Internet, a domain name is a string that identifies a realm of administrative autonomy, authority, or control. Domain names are often used to identify services provided through the Internet, such as websites, email services, and more. ...
s have subsequently been redirected by their
DNS
The Domain Name System (DNS) is a hierarchical and distributed name service that provides a naming system for computers, services, and other resources on the Internet or other Internet Protocol (IP) networks. It associates various informatio ...
service provider to
Dynadot
Dynadot is an ICANN-accredited domain registrar and web host company founded by software engineer Todd Han in 2002. Dynadot's headquarters is located in San Mateo, California, with offices in Zhengzhou and Beijing, China, as well as Toronto, Ca ...
as part of a global effort to disable the malware.
Step 7 software infection

According to researcher Ralph Langner, once installed on a Windows system, Stuxnet infects project files belonging to Siemens'
WinCC/
PCS 7 SCADA control software (Step 7), and subverts a key communication library of WinCC called
s7otbxdx.dll
. Doing so intercepts communications between the WinCC software running under Windows and the target Siemens PLC devices, when the two are connected via a data cable. The malware is able to modify the code on PLC devices unnoticed, and subsequently to mask its presence from WinCC if the control software attempts to read an infected block of memory from the PLC system.
The malware furthermore used a
zero-day exploit in the WinCC/SCADA database software in the form of a hard-coded database password.
PLC infection

Stuxnet's payload targets only those SCADA configurations that meet criteria that it is programmed to identify.
Stuxnet requires specific subordinate system to be attached to the targeted Siemens S7-300 controller system:
variable-frequency drive
A variable-frequency drive (VFD, or adjustable-frequency drive, adjustable-speed drive, variable-speed drive, AC drive, micro drive, inverter drive, variable voltage variable frequency drive, or drive) is a type of AC motor, AC motor drive (sys ...
s (frequency converter drives) and its associated modules. It only attacks those PLC systems with variable-frequency drives from two specific vendors:
Vacon
Vacon was a Finnish manufacturer of variable-speed AC drives for adjustable control of electric motors, and inverters for producing energy from renewable sources and was headquartered in Vaasa, Finland. Vacon stands for Vaasa Control Ltd.
Vacon ...
based in Finland and Fararo Paya based in Iran.
Furthermore, it monitors the frequency of the attached motors, and only attacks systems that spin between 807
Hz and 1,210 Hz. This is a much higher frequency than motors typically operate at in most industrial applications, with the notable exception of
gas centrifuge
A gas centrifuge is a device that performs isotope separation of gases. A centrifuge relies on the principles of centrifugal force accelerating molecules so that particles of different masses are physically separated in a gradient along the radiu ...
s.
Stuxnet installs malware into memory block DB890 of the PLC that monitors the
Profibus
Profibus (usually styled as ''PROFIBUS'', as a portmanteau for Process Field Bus) is a standard for fieldbus communication in automation technology and was first promoted in 1989 by BMBF (German department of education and research) and then u ...
messaging bus of the system.
When certain criteria are met, it periodically modifies the frequency to 1,410 Hz and then to 2 Hz and then to 1,064 Hz, and thus affects the operation of the connected motors by changing their rotational speed.
It also installs a rootkit – the first such documented case on this platform – that hides the malware on the system and masks the changes in rotational speed from monitoring systems.
Removal
Siemens has released a detection and removal tool for Stuxnet. Siemens recommends contacting customer support if an infection is detected and advises installing Microsoft updates for security vulnerabilities and prohibiting the use of third-party
USB flash drive
A flash drive (also thumb drive, memory stick, and pen drive/pendrive) is a data storage device that includes flash memory with an integrated USB interface. A typical USB drive is removable, rewritable, and smaller than an optical disc, and u ...
s.
Siemens also advises immediately upgrading password access codes.
The worm's ability to reprogram external PLCs may complicate the removal procedure. Symantec's Liam O'Murchu warns that fixing Windows systems may not fully solve the infection; a thorough audit of PLCs may be necessary. Despite speculation that incorrect removal of the worm could cause damage,
Siemens reports that in the first four months since discovery, the malware was successfully removed from the systems of 22 customers without any adverse effects.
Control system security
Prevention of control system security incidents, such as from viral infections like Stuxnet, is a topic that is being addressed in both the public and the private sector.
The US Department of Homeland Security
National Cyber Security Division
The National Cyber Security Division (NCSD) is a division of the Office of Cyber Security & Communications, within the United States Department of Homeland Security's Cybersecurity and Infrastructure Security Agency. Formed from the Critical In ...
(NCSD) operates the Control System Security Program (CSSP). The program operates a specialized
computer emergency response team called the
Industrial Control Systems Cyber Emergency Response Team (ICS-CERT), conducts a biannual conference (), provides training, publishes recommended practices, and provides a self-assessment tool. As part of a Department of Homeland Security plan to improve American computer security, in 2008 it and the
Idaho National Laboratory
Idaho National Laboratory (INL) is one of the national laboratories of the United States Department of Energy and is managed by the Battelle Energy Alliance. Historically, the lab has been involved with nuclear research, although the labora ...
(INL) worked with Siemens to identify security holes in the company's widely used Process Control System 7 (PCS 7) and its software Step 7. In July 2008, INL and Siemens publicly announced flaws in the control system at a Chicago conference; Stuxnet exploited these holes in 2009.
Several industry organizations and professional societies have published standards and best practice guidelines providing direction and guidance for control system end-users on how to establish a
control system security management program. The basic premise that all of these documents share is that prevention requires a multi-layered approach, often termed ''
defense in depth
Defence in depth (also known as deep defence or elastic defence) is a military strategy that seeks to delay rather than prevent the advance of an attacker, buying time and causing additional casualties by yielding space. Rather than defeating a ...
''. The layers include policies and procedures, awareness and training,
network segmentation,
access control
In physical security and information security, access control (AC) is the action of deciding whether a subject should be granted or denied access to an object (for example, a place or a resource). The act of ''accessing'' may mean consuming ...
measures,
physical security
Physical security describes security measures that are designed to deny unauthorized access to facilities, equipment, and resources and to protect personnel and property from damage or harm (such as espionage, theft, or terrorist attacks). Physi ...
measures,
system hardening, e.g.,
patch management, and system monitoring, anti-virus and
intrusion prevention system
An intrusion detection system (IDS) is a device or software application that monitors a network or systems for malicious activity or policy violations. Any intrusion activity or violation is typically either reported to an administrator or collec ...
(IPS). The standards and best practices also all recommend starting with a risk analysis and a control system security assessment.
Target and origin
Experts believe that Stuxnet required the largest and costliest development effort in malware history. Developing its abilities would have required a team of capable programmers, in-depth knowledge of
industrial process
Industrial processes are procedures involving chemical, physical, electrical, or mechanical steps to aid in the manufacturing of an item or items, usually carried out on a very large scale. Industrial processes are the key components of heavy ...
es, and an interest in attacking industrial infrastructure.
Eric Byres, who has years of experience maintaining and troubleshooting Siemens systems, told ''
Wired
Wired may refer to:
Arts, entertainment, and media Music
* ''Wired'' (Jeff Beck album), 1976
* ''Wired'' (Hugh Cornwell album), 1993
* ''Wired'' (Mallory Knox album), 2017
* "Wired", a song by Prism from their album '' Beat Street''
* "Wired ...
'' that writing the code would have taken many man-months, if not man-years.
Symantec estimates that the group developing Stuxnet would have consisted of between five and thirty people, and would have taken six months to prepare.
''The Guardian'', the BBC and ''The New York Times'' all claimed that (unnamed) experts studying Stuxnet believe the complexity of the code indicates that only a nation-state would have the abilities to produce it.
The self-destruct and other safeguards within the code implied that a Western government was responsible, or at least is responsible for its development. However, software security expert
Bruce Schneier
Bruce Schneier (; born January 15, 1963) is an American cryptographer, computer security professional, privacy specialist, and writer. Schneier is an Adjunct Lecturer in Public Policy at the Harvard Kennedy School and a Fellow at the Berkman ...
initially condemned the 2010 news coverage of Stuxnet as hype, stating that it was almost entirely based on speculation. But after subsequent research, Schneier stated in 2012 that "we can now conclusively link Stuxnet to the centrifuge structure at the Natanz nuclear enrichment lab in Iran".
In January 2024,
de Volkskrant
''De Volkskrant'' (; ), stylized as de Volkskrant, is a Dutch daily morning newspaper. Founded in 1919, it has a nationwide circulation of about 250,000.
Formerly a leading centre-left Catholic broadsheet, ''de Volkskrant'' today is a medium- ...
reported that Dutch engineer
Erik van Sabben was the saboteur who had infiltrated the underground nuclear complex in the city of Natanz and installed equipment infected with Stuxnet.
Iran as a target
Ralph Langner, the researcher who identified that Stuxnet infected PLCs,
first speculated publicly in September 2010 that the malware was of Israeli origin, and that it targeted Iranian nuclear facilities. However Langner more recently, at a
TED conference, recorded in February 2011, stated that, "My opinion is that the
Mossad
The Institute for Intelligence and Special Operations (), popularly known as Mossad ( , ), is the national intelligence agency of the Israel, State of Israel. It is one of the main entities in the Israeli Intelligence Community, along with M ...
is involved, but that the leading force is not Israel. The leading force behind Stuxnet is the cyber superpower – there is only one; and that's the United States." Kevin Hogan, Senior Director of Security Response at Symantec, reported that most infected systems were in
Iran
Iran, officially the Islamic Republic of Iran (IRI) and also known as Persia, is a country in West Asia. It borders Iraq to the west, Turkey, Azerbaijan, and Armenia to the northwest, the Caspian Sea to the north, Turkmenistan to the nort ...
(about 60%), which has led to speculation that it may have been deliberately targeting "high-value infrastructure" in Iran
including either the
Bushehr Nuclear Power Plant or the
Natanz nuclear facility.
Langner called the malware "a one-shot weapon" and said that the intended target was probably hit, although he admitted this was speculation.
Another German researcher and spokesman of the German-based
Chaos Computer Club
The Chaos Computer Club (CCC) is Europe's largest association of Hacker (computer security), hackers with 7,700 registered members. Founded in 1981, the association is incorporated as an ''eingetragener Verein'' in Germany, with local chapters ...
, Frank Rieger, was the first to speculate that Natanz was the target.
Natanz nuclear facilities

According to the Israeli newspaper ''
Haaretz
''Haaretz'' (; originally ''Ḥadshot Haaretz'' – , , ) is an List of newspapers in Israel, Israeli newspaper. It was founded in 1918, making it the longest running newspaper currently in print in Israel. The paper is published in Hebrew lan ...
'', in September 2010 experts on Iran and computer security specialists were increasingly convinced that Stuxnet was meant "to
sabotage
Sabotage is a deliberate action aimed at weakening a polity, government, effort, or organization through subversion, obstruction, demoralization (warfare), demoralization, destabilization, divide and rule, division, social disruption, disrupti ...
the uranium enrichment facility at Natanz – where the centrifuge operational capacity had dropped over the past year by 30 percent." On 23 November 2010 it was announced that uranium enrichment at Natanz had ceased several times because of a series of major technical problems. A "serious nuclear accident" (supposedly the shutdown of some of its centrifuges
) occurred at the site in the first half of 2009, which is speculated to have forced
Gholam Reza Aghazadeh, the head of the
Atomic Energy Organization of Iran (AEOI), to resign. Statistics published by the
Federation of American Scientists
The Federation of American Scientists (FAS) is an American nonprofit global policy think tank with the stated intent of using science and scientific analysis to attempt to make the world more secure. FAS was founded in 1945 by a group of scient ...
(FAS) show that the number of enrichment centrifuges operational in Iran mysteriously declined from about 4,700 to about 3,900 beginning around the time the nuclear incident WikiLeaks mentioned would have occurred. The
Institute for Science and International Security
The Institute for Science and International Security (ISIS) is a nonprofit, non-governmental institution to inform the public about "science and policy issues affecting international security".
Founded in 1993, the group is led by founder and f ...
(ISIS) suggests, in a report published in December 2010, that Stuxnet is a reasonable explanation for the apparent damage
at Natanz, and may have destroyed up to 1,000 centrifuges (10 percent) sometime between November 2009 and late January 2010. The authors conclude:
The
Institute for Science and International Security
The Institute for Science and International Security (ISIS) is a nonprofit, non-governmental institution to inform the public about "science and policy issues affecting international security".
Founded in 1993, the group is led by founder and f ...
(ISIS) report further notes that Iranian authorities have attempted to conceal the breakdown by installing new centrifuges on a large scale.
The worm worked by first causing an infected Iranian IR-1 centrifuge to increase from its normal operating speed of 1,064 hertz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or Cycle per second, cycle) per second. The hertz is an SI derived unit whose formal expression in ter ...
to 1,410 hertz for 15 minutes before returning to its normal frequency. Twenty-seven days later, the worm went back into action, slowing the infected centrifuges down to a few hundred hertz for a full 50 minutes. The stresses from the excessive, then slower, speeds caused the aluminium centrifugal tubes to expand, often forcing parts of the centrifuges into sufficient contact with each other to destroy the machine.
According to ''The Washington Post
''The Washington Post'', locally known as ''The'' ''Post'' and, informally, ''WaPo'' or ''WP'', is an American daily newspaper published in Washington, D.C., the national capital. It is the most widely circulated newspaper in the Washington m ...
'', International Atomic Energy Agency
The International Atomic Energy Agency (IAEA) is an intergovernmental organization that seeks to promote the peaceful use of nuclear technology, nuclear energy and to inhibit its use for any military purpose, including nuclear weapons. It was ...
(IAEA) cameras installed in the Natanz facility recorded the sudden dismantling and removal of approximately 900–1,000 centrifuges during the time the Stuxnet worm was reportedly active at the plant. Iranian technicians, however, were able to quickly replace the centrifuges and the report concluded that uranium enrichment was likely only briefly disrupted.
On 15 February 2011, the Institute for Science and International Security
The Institute for Science and International Security (ISIS) is a nonprofit, non-governmental institution to inform the public about "science and policy issues affecting international security".
Founded in 1993, the group is led by founder and f ...
released a report concluding that:
Iranian reaction
The Associated Press
The Associated Press (AP) is an American not-for-profit organization, not-for-profit news agency headquartered in New York City.
Founded in 1846, it operates as a cooperative, unincorporated association, and produces news reports that are dist ...
reported that the semi-official Iranian Students News Agency
The Iranian Students' News Agency () (ISNA, Persian: ) established in December 1999, is a news agency run by Iranian university students.
Position
Based in Tehran and founded in 1999 by Abolfazl Fateh-an ex-aide to former Iranian presidential ...
released a statement on 24 September 2010 stating that experts from the Atomic Energy Organization of Iran met in the previous week to discuss how Stuxnet could be removed from their systems. According to analysts, such as David Albright
David Albright (born 1948) is an American physicist and a weapons expert who is the founder of the non-governmental Institute for Science and International Security (ISIS), its current president, and author of several books on proliferation o ...
, Western intelligence agencies had been attempting to sabotage the Iranian nuclear program for some time.
The head of the Bushehr Nuclear Power Plant told Reuters
Reuters ( ) is a news agency owned by Thomson Reuters. It employs around 2,500 journalists and 600 photojournalists in about 200 locations worldwide writing in 16 languages. Reuters is one of the largest news agencies in the world.
The agency ...
that only the personal computers of staff at the plant had been infected by Stuxnet and the state-run newspaper ''Iran Daily'' quoted Reza Taghipour, Iran's telecommunications minister, as saying that it had not caused "serious damage to government systems". The Director of Information Technology Council at the Iranian Ministry of Industries and Mines, Mahmud Liaii, has said that: "An electronic war has been launched against Iran... This computer worm is designed to transfer data about production lines from our industrial plants to locations outside Iran."
In response to the infection, Iran assembled a team to combat it. With more than 30,000 IP addresses affected in Iran, an official said that the infection was fast spreading in Iran and the problem had been compounded by the ability of Stuxnet to mutate. Iran had set up its own systems to clean up infections and had advised against using the Siemens SCADA antivirus since it is suspected that the antivirus contains embedded code which updates Stuxnet instead of removing it.
According to Hamid Alipour, deputy head of Iran's government Information Technology Company, "The attack is still ongoing and new versions of this virus are spreading." He reported that his company had begun the cleanup process at Iran's "sensitive centres and organizations." "We had anticipated that we could root out the virus within one to two months, but the virus is not stable, and since we started the cleanup process three new versions of it have been spreading", he told the Islamic Republic News Agency on 27 September 2010.
On 29 November 2010, Iranian president Mahmoud Ahmadinejad
Mahmoud Ahmadinejad (born Mahmoud Sabbaghian on 28 October 1956) is an Iranian Iranian principlists, principlist and Iranian nationalism, nationalist politician who served as the sixth president of Iran from 2005 to 2013. He is currently a mem ...
stated for the first time that a computer virus had caused problems with the controller handling the centrifuges at its Natanz facilities. According to Reuters, he told reporters at a news conference in Tehran, "They succeeded in creating problems for a limited number of our centrifuges with the software they had installed in electronic parts."
On the same day two Iranian nuclear scientists were targeted in separate, but nearly simultaneous car bomb attacks near Shahid Beheshti University
Shahid Beheshti University (SBU) (), originally founded as the Melli University (National University of Iran) (), is a Public university, public research university in Tehran, Iran. The university offers programs at Bachelor's, Master's and Ph. ...
in Tehran. Majid Shahriari, a quantum physicist, was killed. Fereydoon Abbasi, a high-ranking official at the Ministry of Defense was seriously wounded. ''Wired'' speculated that the assassinations could indicate that whoever was behind Stuxnet felt that it was not sufficient to stop the nuclear program. That same ''Wired'' article suggested the Iranian government could have been behind the assassinations. In January 2010, another Iranian nuclear scientist, a physics professor at Tehran University
The University of Tehran (UT) or Tehran University (, ) is a public collegiate university in Iran, and the oldest and most prominent Iranian university located in Tehran. Based on its historical, socio-cultural, and political pedigree, as well as ...
, was killed in a similar bomb explosion. On 11 January 2012, a director of the Natanz nuclear enrichment facility, Mostafa Ahmadi Roshan, was killed in an attack quite similar to the one that killed Shahriari.
An analysis by the FAS demonstrates that Iran's enrichment capacity grew during 2010. The study indicated that Iran's centrifuges appeared to be performing 60% better than in the previous year, which would significantly reduce Tehran's time to produce bomb-grade uranium. The FAS report was reviewed by an official with the IAEA who affirmed the study.
European and US officials, along with private experts, told Reuters that Iranian engineers were successful in neutralizing and purging Stuxnet from their country's nuclear machinery.
Given the growth in Iranian enrichment ability in 2010, the country may have intentionally put out misinformation to cause Stuxnet's creators to believe that the worm was more successful in disabling the Iranian nuclear program than it actually was.
Israel
Israel
Israel, officially the State of Israel, is a country in West Asia. It Borders of Israel, shares borders with Lebanon to the north, Syria to the north-east, Jordan to the east, Egypt to the south-west, and the Mediterranean Sea to the west. Isr ...
, through Unit 8200
Unit 8200 (, ''Yehida shmone matayim'' "Unit eight two-hundred") is an Israeli Intelligence Corps unit of the Israel Defense Forces responsible for clandestine operation, collecting signal intelligence (SIGINT) and code decryption, counteri ...
, has been speculated to be the country behind Stuxnet in multiple media reports and by experts such as Richard A. Falkenrath, former Senior Director for Policy and Plans within the US Office of Homeland Security
The United States Department of Homeland Security (DHS) is the U.S. federal executive department responsible for public security, roughly comparable to the interior, home, or public security ministries in other countries. Its missions involv ...
. Yossi Melman, who covers intelligence for Israeli newspaper ''Haaretz'' and wrote a book about Israeli intelligence, also suspected that Israel was involved, noting that Meir Dagan
Aluf Meir Dagan (; 30 January 1945 – 17 March 2016) was an Israel Defense Forces Major General (reserve) and Director of the Mossad.
Personal life and education
Meir Huberman (later Dagan) was born on a train on the outskirts of Kherson, b ...
, the former (up until 2011) head of the national intelligence agency Mossad
The Institute for Intelligence and Special Operations (), popularly known as Mossad ( , ), is the national intelligence agency of the Israel, State of Israel. It is one of the main entities in the Israeli Intelligence Community, along with M ...
, had his term extended in 2009 because he was said to be involved in important projects. Additionally, in 2010 Israel grew to expect that Iran would have a nuclear weapon in 2014 or 2015 – at least three years later than earlier estimates – without the need for an Israeli military attack on Iranian nuclear facilities; "They seem to know something, that they have more time than originally thought", he added. Israel has not publicly commented on the Stuxnet attack but in 2010 confirmed that cyberwarfare was now among the pillars of its defense doctrine, with a military intelligence unit set up to pursue both defensive and offensive options. When questioned whether Israel was behind the virus in the fall of 2010, some Israeli officials broke into "wide smiles", fueling speculation that the government of Israel was involved with its genesis. American presidential advisor Gary Samore also smiled when Stuxnet was mentioned, although American officials have suggested that the virus originated abroad. According to ''The Telegraph'', Israeli newspaper ''Haaretz'' reported that a video celebrating operational successes of Gabi Ashkenazi, retiring Israel Defense Forces
The Israel Defense Forces (IDF; , ), alternatively referred to by the Hebrew-language acronym (), is the national military of the State of Israel. It consists of three service branches: the Israeli Ground Forces, the Israeli Air Force, and ...
(IDF) Chief of Staff, was shown at his retirement party and included references to Stuxnet, thus strengthening claims that Israel's security forces were responsible.
In 2009, a year before Stuxnet was discovered, Scott Borg of the United States Cyber-Consequences Unit (US-CCU) suggested that Israel may prefer to mount a cyberattack rather than a military strike on Iran's nuclear facilities. In late 2010 Borg stated, "Israel certainly has the ability to create Stuxnet and there is little downside to such an attack because it would be virtually impossible to prove who did it. So a tool like Stuxnet is Israel's obvious weapon of choice." Iran uses P-1 centrifuges at Natanz, the design for which A. Q. Khan
Abdul Qadeer Khan (1 April 1936 – 10 October 2021) was a Pakistani nuclear physicist and metallurgical engineer. He is colloquially known as the "father of Pakistan's atomic weapons program".
A Muhajir emigrant from India who migrated t ...
stole in 1976 and took to Pakistan. His black market
A black market is a Secrecy, clandestine Market (economics), market or series of transactions that has some aspect of illegality, or is not compliant with an institutional set of rules. If the rule defines the set of goods and services who ...
nuclear-proliferation network sold P-1s to, among other customers, Iran. Experts believe that Israel also somehow acquired P-1s and tested Stuxnet on the centrifuges, installed at the Dimona
Dimona (, ) is an Israeli city in the Negev desert, to the south-east of Beersheba and west of the Dead Sea above the Arabah, Arava valley in the Southern District (Israel), Southern District of Israel. In , its population was . The Shimon Pere ...
facility that is part of its own nuclear program. The equipment may be from the United States, which received P-1s from Libya's former nuclear program.
Some have also cited several clues in the code such as a concealed reference to the word ''MYRTUS'', believed to refer to the Latin
Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
name ''myrtus
''Myrtus'' (commonly called myrtle) is a genus of flowering plants in the family Myrtaceae. It was first described by Swedish botanist Linnaeus in 1753.
Over 600 names have been proposed in the genus, but nearly all have either been moved ...
'' of the Myrtle tree, which in Hebrew is called ''hadassah''. Hadassah was the birth name of the former Jewish queen of Persia, Queen Esther
Esther (; ), originally Hadassah (; ), is the eponymous heroine of the Book of Esther in the Hebrew Bible. According to the biblical narrative, which is set in the Achaemenid Empire, the Persian king Ahasuerus falls in love with Esther and ma ...
. However, it may be that the "MYRTUS" reference is simply a misinterpreted reference to SCADA
SCADA (an acronym for supervisory control and data acquisition) is a control system architecture comprising computers, networked data communications and graphical user interfaces for high-level supervision of machines and processes. It also cove ...
components known as ''RTUs'' (Remote Terminal Units) and that this reference is actually "My RTUs"–a management feature of SCADA. Also, the number 19790509 appears once in the code and may refer to the date ''1979 May 09'', the day Habib Elghanian, a Persian Jew, was executed in Tehran
Tehran (; , ''Tehrân'') is the capital and largest city of Iran. It is the capital of Tehran province, and the administrative center for Tehran County and its Central District (Tehran County), Central District. With a population of around 9. ...
. Another date that appears in the code is "24 September 2007", the day that Iran's president Mahmoud Ahmadinejad
Mahmoud Ahmadinejad (born Mahmoud Sabbaghian on 28 October 1956) is an Iranian Iranian principlists, principlist and Iranian nationalism, nationalist politician who served as the sixth president of Iran from 2005 to 2013. He is currently a mem ...
spoke at Columbia University
Columbia University in the City of New York, commonly referred to as Columbia University, is a Private university, private Ivy League research university in New York City. Established in 1754 as King's College on the grounds of Trinity Churc ...
and made comments questioning the validity of the Holocaust
The Holocaust (), known in Hebrew language, Hebrew as the (), was the genocide of History of the Jews in Europe, European Jews during World War II. From 1941 to 1945, Nazi Germany and Collaboration with Nazi Germany and Fascist Italy ...
. Such data is not conclusive, since, as noted by Symantec, "...attackers would have the natural desire to implicate another party".
United States
There has also been reports on the involvement of the United States and its collaboration with Israel, with one report stating that "there is vanishingly little doubt that tplayed a role in creating the worm." It has been reported that the United States, under one of its most secret programs, initiated by the Bush administration and accelerated by the Obama administration
Barack Obama's tenure as the 44th president of the United States began with his first inauguration on January 20, 2009, and ended on January 20, 2017. Obama, a Democrat from Illinois, took office following his victory over Republican nomine ...
, has sought to destroy Iran's nuclear program by novel methods such as undermining Iranian computer systems. A leaked diplomatic cable showed how the United States was advised to target Iran's nuclear abilities through 'covert sabotage'. An article in ''The New York Times'' in January 2009 credited a then-unspecified program with preventing an Israeli military attack on Iran where some of the efforts focused on ways to destabilize the centrifuges. A ''Wired
Wired may refer to:
Arts, entertainment, and media Music
* ''Wired'' (Jeff Beck album), 1976
* ''Wired'' (Hugh Cornwell album), 1993
* ''Wired'' (Mallory Knox album), 2017
* "Wired", a song by Prism from their album '' Beat Street''
* "Wired ...
'' article claimed that Stuxnet "is believed to have been created by the United States". Dutch historian Peter Koop speculated that the Tailored Access Operations
The Office of Tailored Access Operations (TAO), structured as S32, is a cyber-warfare intelligence-gathering unit of the National Security Agency (NSA). It has been active since at least 1998, possibly 1997, but was not named or structured as ...
could have developed Stuxnet, possibly in collaboration with Israel.
The fact that John Bumgarner, a former intelligence officer and member of the United States Cyber-Consequences Unit (US-CCU), published an article prior to Stuxnet being discovered or deciphered, that outlined a strategic cyber strike on centrifuges and suggests that cyber attacks are permissible against nation states which are operating uranium enrichment programs that violate international treaties gives some credibility to these claims. Bumgarner pointed out that the centrifuges used to process fuel for nuclear weapons are a key target for ''cybertage'' operations and that they can be made to destroy themselves by manipulating their rotational speeds.
In a March 2012 interview with ''60 Minutes
''60 Minutes'' is an American television news magazine broadcast on the CBS television network. Debuting in 1968, the program was created by Don Hewitt and Bill Leonard, who distinguished it from other news programs by using a unique style o ...
'', retired US Air Force
The United States Air Force (USAF) is the Air force, air service branch of the United States Department of Defense. It is one of the six United States Armed Forces and one of the eight uniformed services of the United States. Tracing its ori ...
General Michael Hayden – who served as director of both the Central Intelligence Agency
The Central Intelligence Agency (CIA; ) is a civilian foreign intelligence service of the federal government of the United States tasked with advancing national security through collecting and analyzing intelligence from around the world and ...
and National Security Agency
The National Security Agency (NSA) is an intelligence agency of the United States Department of Defense, under the authority of the director of national intelligence (DNI). The NSA is responsible for global monitoring, collection, and proces ...
– while denying knowledge of who created Stuxnet said that he believed it had been "a good idea" but that it carried a downside in that it had legitimized the use of sophisticated cyber weapons designed to cause physical damage. Hayden said, "There are those out there who can take a look at this... and maybe even attempt to turn it to their own purposes". In the same report, Sean McGurk, a former cybersecurity official at the Department of Homeland Security
The United States Department of Homeland Security (DHS) is the U.S. federal executive department responsible for public security, roughly comparable to the interior, home, or public security ministries in other countries. Its missions invol ...
noted that the Stuxnet source code could now be downloaded online and modified to be directed at new target systems. Speaking of the Stuxnet creators, he said, "They opened the box. They demonstrated the capability... It's not something that can be put back."
Joint effort and other states and targets
In April 2011, Iranian government official Gholam Reza Jalali stated that an investigation had concluded that the United States and Israel were behind the Stuxnet attack. Frank Rieger stated that three European countries' intelligence agencies agreed that Stuxnet was a joint United States-Israel effort. The code for the Windows injector and the PLC payload differ in style, likely implying collaboration. Other experts believe that a US-Israel cooperation is unlikely because "the level of trust between the two countries' intelligence and military establishments is not high."
A ''Wired'' magazine article about US General Keith B. Alexander stated: "And he and his cyber warriors have already launched their first attack. The cyber weapon that came to be known as Stuxnet was created and built by the NSA in partnership with the CIA and Israeli intelligence in the mid-2000s."
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
, Jordan
Jordan, officially the Hashemite Kingdom of Jordan, is a country in the Southern Levant region of West Asia. Jordan is bordered by Syria to the north, Iraq to the east, Saudi Arabia to the south, and Israel and the occupied Palestinian ter ...
, and France
France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...
are other possibilities, and Siemens may have also participated. Langner speculated that the infection may have spread from USB drives belonging to Russian contractors since the Iranian targets were not accessible via the Internet. In 2019, it was reported that an Iranian mole working for Dutch intelligence at the behest of Israel and the CIA inserted the Stuxnet virus with a USB flash drive or convinced another person working at the Natanz facility to do so.
Sandro Gaycken from the Free University Berlin argued that the attack on Iran was a ruse to distract from Stuxnet's real purpose. According to him, its broad dissemination in more than 100,000 industrial plants worldwide suggests a field test of a cyber weapon in different security cultures, testing their preparedness, resilience, and reactions, all highly valuable information for a cyberwar unit.
The United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
has denied involvement in the worm's creation.
In July 2013, Edward Snowden
Edward Joseph Snowden (born June 21, 1983) is a former National Security Agency (NSA) intelligence contractor and whistleblower who leaked classified documents revealing the existence of global surveillance programs.
Born in 1983 in Elizabeth ...
claimed that Stuxnet was cooperatively developed by the United States and Israel.
Deployment in North Korea
According to a report by Reuters, the NSA also tried to sabotage North Korea
North Korea, officially the Democratic People's Republic of Korea (DPRK), is a country in East Asia. It constitutes the northern half of the Korea, Korean Peninsula and borders China and Russia to the north at the Yalu River, Yalu (Amnok) an ...
's nuclear program using a version of Stuxnet. The operation was reportedly launched in tandem with the attack that targeted Iranian centrifuges in 2009–10. The North Korean nuclear program shares a number of similarities with the Iranian, both having been developed with technology transferred by Pakistani nuclear scientist A.Q. Khan. The effort failed, however, because North Korea's extreme secrecy and isolation made it impossible to introduce Stuxnet into the nuclear facility.
Stuxnet 2.0 cyberattack
In 2018, Gholamreza Jalali, Iran's chief of the National Passive Defence Organisation (NPDO), claimed that his country fended off a Stuxnet-like attack targeting the country's telecom infrastructure. Iran's Telecommunications minister Mohammad-Javad Azari Jahromi has since accused Israel of orchestrating the attack. Iran plans to sue Israel through the International Court of Justice
The International Court of Justice (ICJ; , CIJ), or colloquially the World Court, is the only international court that Adjudication, adjudicates general disputes between nations, and gives advisory opinions on International law, internation ...
(ICJ) and is also willing to launch a retaliation attack if Israel does not desist.
Related malware
"Stuxnet's Secret Twin"
A November 2013 article in Foreign Policy magazine claims existence of an earlier, much more sophisticated attack on the centrifuge complex at Natanz, focused on increasing centrifuge failure rate over a long time period by stealthily inducing uranium hexafluoride gas overpressure incidents. This malware was capable of spreading only by being physically installed, probably by previously contaminated field equipment used by contractors working on Siemens control systems within the complex. It is not clear whether this attack attempt was successful, but follow-up by a different, simpler, and more conventional attack is indicative that it was not.
Duqu
On 1 September 2011, a new worm was found, thought to be related to Stuxnet. The Laboratory of Cryptography and System Security (CrySyS) of the Budapest University of Technology and Economics
The Budapest University of Technology and Economics ( or in short ), official abbreviation BME, is a public research university located in Budapest, Hungary. It is the most significant university of technology in the country and is considered ...
analyzed the malware, naming the threat Duqu. Symantec, based on this report, continued the analysis of the threat, calling it "nearly identical to Stuxnet, but with a completely different purpose", and published a detailed technical paper. The main component used in Duqu is designed to capture information such as keystrokes and system information. The exfiltrated data may be used to enable a future Stuxnet-like attack. On 28 December 2011, Kaspersky Lab's director of global research and analysis spoke to Reuters about recent research results showing that the platform Stuxnet and Duqu both originated in 2007, and is being referred to as Tilded due to the ~d at the beginning of the file names. Also uncovered in this research was the possibility for three more variants based on the Tilded platform.
Flame
In May 2012, the new malware "Flame" was found, thought to be related to Stuxnet. Researchers named the program "Flame" after the name of one of its modules. After analysing the code of Flame, Kaspersky Lab said that there is a strong relationship between Flame and Stuxnet. An early version of Stuxnet contained code to propagate infections via USB drives that is nearly identical to a Flame module that exploits the same vulnerability.
Media coverage
Since 2010, there has been extensive international media coverage on Stuxnet and its aftermath. In early commentary, ''The Economist
''The Economist'' is a British newspaper published weekly in printed magazine format and daily on Electronic publishing, digital platforms. It publishes stories on topics that include economics, business, geopolitics, technology and culture. M ...
'' pointed out that Stuxnet was "a new kind of cyber-attack." On 8 July 2011, ''Wired
Wired may refer to:
Arts, entertainment, and media Music
* ''Wired'' (Jeff Beck album), 1976
* ''Wired'' (Hugh Cornwell album), 1993
* ''Wired'' (Mallory Knox album), 2017
* "Wired", a song by Prism from their album '' Beat Street''
* "Wired ...
'' then published an article detailing how network security experts were able to decipher the origins of Stuxnet. In that piece, Kim Zetter claimed that Stuxnet's "cost–benefit ratio is still in question." Later commentators tended to focus on the strategic significance of Stuxnet as a cyber weapon. Following the Wired piece, Holger Stark called Stuxnet the "first digital weapon of geopolitical importance, it could change the way wars are fought." Meanwhile, Eddie Walsh referred to Stuxnet as "the world's newest high-end asymmetric threat." Ultimately, some claim that the "extensive media coverage afforded to Stuxnet has only served as an advertisement for the vulnerabilities used by various cybercriminal groups." While that may be the case, the media coverage has also increased awareness of cyber security threats.
Alex Gibney
Philip Alexander Gibney (; born October 23, 1953) is an American documentary film director and producer. In 2010, ''Esquire'' magazine said Gibney "is becoming the most important documentarian of our time."
Gibney's works as director include ''T ...
's 2016 documentary '' Zero Days'' covers the phenomenon around Stuxnet. A zero-day (also known as 0-day) vulnerability is a computer-software vulnerability that is unknown to, or unaddressed by, those who should be interested in mitigating the vulnerability (including the vendor of the target software). Until the vulnerability is mitigated, hackers can exploit it to adversely affect computer programs, data, additional computers or a network.
In 2016, it was revealed that General James Cartwright
James Edward "Hoss" Cartwright (born September 22, 1949) is a retired United States Marine Corps General (United States), general who last served as the eighth vice chairman of the Joint Chiefs of Staff from August 31, 2007, to August 3, 2011. H ...
, the former head of the U.S. Strategic Command, had leaked information related to Stuxnet. He later pleaded guilty for lying to FBI agents pursuing an investigation into the leak. On 17 January 2017, he was granted a full pardon in this case by President Obama, thus expunging his conviction.
In popular culture
Besides the aforementioned Alex Gibney
Philip Alexander Gibney (; born October 23, 1953) is an American documentary film director and producer. In 2010, ''Esquire'' magazine said Gibney "is becoming the most important documentarian of our time."
Gibney's works as director include ''T ...
documentary '' Zero Days'' (2016), which looks into the malware and the cyberwarfare surrounding it, other works which reference Stuxnet include:
* In ''Castle
A castle is a type of fortification, fortified structure built during the Middle Ages predominantly by the nobility or royalty and by Military order (monastic society), military orders. Scholars usually consider a ''castle'' to be the private ...
'', season 8, episode 18 "Backstabber" Stuxnet is revealed to have been (fictionally) created by MI6
The Secret Intelligence Service (SIS), commonly known as MI6 ( Military Intelligence, Section 6), is the foreign intelligence service of the United Kingdom, tasked mainly with the covert overseas collection and analysis of human intelligenc ...
, and a version of it is used to take down the London power grid.
* ''Trojan Horse'' is a novel written by Windows utility writer and novelist Mark Russinovich
Mark Eugene Russinovich (born December 22, 1966) is a Spanish-born American software engineer and author who serves as CTO of Microsoft Azure. He was a cofounder of software producers Winternals before Microsoft acquired it in 2006.
Early lif ...
. It features the usage of the Stuxnet virus as a main plot line for the story, and the attempt of Iran to bypass it.
* In '' Ghost in the Shell: Arise'', Stuxnet is the named type of computer virus which infected Kusanagi and Manamura allowing false memories to be implanted.
* In July 2017, MRSA ( Mat Zo) released a track named "Stuxnet" through Hospital Records
Hospital Records is a British independent record label based in South London. Primarily releasing drum and bass, the label was started in 1996 by Tony Colman ( London Elektricity) and Chris Goss and has grown in recent years to become one of t ...
.
* In Ubisoft's 2013 video game '' Tom Clancy's Splinter Cell: Blacklist'', the protagonist, Sam Fisher, makes use of a mobile, airborne headquarters ("Paladin") which is said at one point within the game's story mode to have been targeted by a Stuxnet-style virus, causing its systems to fail and the plane to careen towards the ocean, and would have crashed without Fisher's intervening.
* In Michael Mann's 2015 movie '' Blackhat'', the code shown as belonging to a virus used by a hacker to cause the coolant pumps explosion in a nuclear plant in Chai Wan, Hong Kong, is actual Stuxnet decompiled code.
* In the third episode of '' Star Trek: Discovery'', " Context Is for Kings", characters identify a segment of code as being part of an experimental transportation system. The code shown is decompiled Stuxnet code. Much of the same code is shown in the episode, "Pyre" of '' The Expanse'', this time as a visual representation of a "diagnostic exploit" breaking into the control software for nuclear missiles.
See also
References
Further reading
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* Ralph Langner'
Stuxnet Deep Dive
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* Kim Zetter, ''Countdown to Zero Day: Stuxnet and the Launch of the World's First Digital Weapon''. New York: Crown Publishing Group
The Crown Publishing Group is a subsidiary of Penguin Random House that publishes across several fiction and non-fiction categories. Originally founded in 1933 as a remaindered books wholesaler called Outlet Book Company, the firm expanded int ...
, 2014. .
External links
fanny.bmp
– at Securelist
fanny.bmp source
– at GitHub
Stuxnet code
– at Internet Archive
{{North Korea–United States relations
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2010 in Iran
2010 in North Korea
Computer access control
Cryptographic attacks
Cyberattacks on energy sector
Cyberattacks
Cyberwarfare in Iran
Cybercrime in India
Cyberwarfare
Exploit-based worms
Hacking in the 2010s
Industrial computing
Iran–Israel relations
Iran–United States relations
North Korea–United States relations
Israel–United States relations
Windows malware
Nuclear program of Iran
Nuclear program of North Korea
Privilege escalation exploits
Rootkits
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Malware targeting industrial control systems