HOME
*





Padding Oracle Attack
In cryptography, a padding oracle attack is an attack which uses the Padding (cryptography), padding validation of a cryptographic message to decrypt the ciphertext. In cryptography, variable-length plaintext messages often have to be padded (expanded) to be compatible with the underlying cryptographic primitive. The attack relies on having a "padding oracle" who freely responds to queries about whether a message is correctly padded or not. Padding oracle attacks are mostly associated with CBC mode of operation, CBC mode decryption used within block ciphers. Padding modes for asymmetric algorithms such as OAEP may also be vulnerable to padding oracle attacks. Symmetric cryptography In symmetric cryptography, the padding oracle attack can be applied to the CBC mode of operation, where the "test oracle, oracle" (usually a server) leaks data about whether the Padding (cryptography), padding of an encrypted message is correct or not. Such data can allow attackers to decrypt (and someti ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Padding (cryptography)
In cryptography, padding is any of a number of distinct practices which all include adding data to the beginning, middle, or end of a message prior to encryption. In classical cryptography, padding may include adding nonsense phrases to a message to obscure the fact that many messages end in predictable ways, e.g. ''sincerely yours''. Classical cryptography Official messages often start and end in predictable ways: ''My dear ambassador, Weather report, Sincerely yours'', etc. The primary use of padding with classical ciphers is to prevent the cryptanalyst from using that predictability to find Known-plaintext attack, known plaintext that aids in breaking the encryption. Random length padding also prevents an attacker from knowing the exact length of the plaintext message. A famous example of classical padding which caused a great misunderstanding is "the world wonders" incident, which nearly caused an Allied loss at the WWII Battle off Samar, part of the larger Battle of Leyte Gul ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Serge Vaudenay
Serge Vaudenay (born 5 April 1968) is a French cryptographer and professor, director of the Communications Systems Section at the École Polytechnique Fédérale de Lausanne Serge Vaudenay entered the École Normale Supérieure in Paris as a ''normalien'' student in 1989. In 1992, he passed the ''agrégation'' in mathematics. He completed his Ph.D. studies at the computer science laboratory of École Normale Supérieure, and defended it in 1995 at the Paris Diderot University; his advisor was Jacques Stern. From 1995 to 1999, he was a senior research fellow at French National Centre for Scientific Research (CNRS). In 1999, he moved to a professorship at the École Polytechnique Fédérale de Lausanne where he leads the Laboratory of Security and Cryptography (LASEC). LASEC is host to two popular security programs developed by its members: *iChair, developed by Thomas Baignères and Matthieu Finiasz, a popular on-line submission and review server used by many cryptography confere ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

POODLE
, nickname = , stock = , country = Germany or France (see history) , height = , maleheight = , femaleheight = , weight = , maleweight = , femaleweight = , coat = Curly , colour = , litter_size = , life_span = , kc_name = Société Centrale Canine , kc_std = https://www.centrale-canine.fr/le-chien-de-race/caniche , kc2_name = , kc2_std = , fcistd = http://www.fci.be/Nomenclature/Standards/172g09-en.pdf , note = The Poodle, called the Pudel in German and the Caniche in French, is a breed of water dog. The breed is divided into four varieties based on size, the Standard Poodle, Medium Poodle, Miniature Poodle and Toy Poodle, although the Medium Poodle variety is not universally recognised. They have a distinctive thick, curly coat, and come in many colors, with only solid ones recognized by breed registries. While a rea ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Downgrade Attack
A downgrade attack, also called a bidding-down attack or version rollback attack, is a form of cryptographic attack on a computer system or communications protocol that makes it abandon a high-quality mode of operation (e.g. an encrypted connection) in favor of an older, lower-quality mode of operation (e.g. cleartext) that is typically provided for backward compatibility with older systems. An example of such a flaw was found in OpenSSL that allowed the attacker to negotiate the use of a lower version of TLS between the client and server. This is one of the most common types of downgrade attacks. Opportunistic encryption protocols such as STARTTLS are generally vulnerable to downgrade attacks, as they, by design, fall back to unencrypted communication. Websites which rely on redirects from unencrypted HTTP to encrypted HTTPS can also be vulnerable to downgrade attacks (e.g., sslstrip), as the initial redirect is not protected by encryption. Attack Downgrade attacks are often ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Signal-to-noise Ratio
Signal-to-noise ratio (SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. SNR is defined as the ratio of signal power to the noise power, often expressed in decibels. A ratio higher than 1:1 (greater than 0 dB) indicates more signal than noise. SNR, bandwidth, and channel capacity of a communication channel are connected by the Shannon–Hartley theorem. Definition Signal-to-noise ratio is defined as the ratio of the power of a signal (meaningful input) to the power of background noise (meaningless or unwanted input): : \mathrm = \frac, where is average power. Both signal and noise power must be measured at the same or equivalent points in a system, and within the same system bandwidth. Depending on whether the signal is a constant () or a random variable (), the signal-to-noise ratio for random noise becomes: : \mathrm = \frac where E refers to the expected value, i.e. in this case ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Lucky Thirteen Attack
A Lucky Thirteen attack is a cryptographic timing attack against implementations of the Transport Layer Security (TLS) protocol that use the CBC mode of operation, first reported in February 2013 by its developers Nadhem J. AlFardan and Kenny Paterson of the Information Security Group at Royal Holloway, University of London. Includes list of which software versions are vulnerable. Attack It is a novel variant of Serge Vaudenay's padding oracle attack that was previously thought to have been fixed, that uses a timing side-channel attack against the message authentication code (MAC) check stage in the TLS algorithm to break the algorithm in a way that was not fixed by previous attempts to mitigate Vaudenay's attack. "In this sense, the attacks do not pose a significant danger to ordinary users of TLS in their current form. However, it is a truism that attacks only get better with time, and we cannot anticipate what improvements to our attacks, or entirely new attacks, may yet be disc ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Transport Layer Security
Transport Layer Security (TLS) is a cryptographic protocol designed to provide communications security over a computer network. The protocol is widely used in applications such as email, instant messaging, and voice over IP, but its use in securing HTTPS remains the most publicly visible. The TLS protocol aims primarily to provide security, including privacy (confidentiality), integrity, and authenticity through the use of cryptography, such as the use of certificates, between two or more communicating computer applications. It runs in the presentation layer and is itself composed of two layers: the TLS record and the TLS handshake protocols. The closely related Datagram Transport Layer Security (DTLS) is a communications protocol providing security to datagram-based applications. In technical writing you often you will see references to (D)TLS when it applies to both versions. TLS is a proposed Internet Engineering Task Force (IETF) standard, first defined in 1999, and the c ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Steam (service)
Steam is a Digital distribution of video games, video game digital distribution service and storefront by Valve Corporation, Valve. It was launched as a software client in September 2003 as a way for Valve to provide automatic updates for their games, and expanded to distributing and offering third-party Video game publisher, game publishers' titles in late 2005. Steam offers various features, like digital rights management (DRM), Matchmaking (video games), game server matchmaking, Valve Anti-Cheat, anti-cheat measures, social networking service, social networking and video game live streaming, game streaming services. It provides the user with automatic game updating, saved game cloud synchronization, and community features such as friends messaging, in-game chat and a community market. Valve released a freely available application programming interface (API) called Steamworks in 2008, which developers can use to integrate Steam's functions into their products, including in-gam ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Ruby On Rails
Ruby on Rails (simplified as Rails) is a server-side web application framework written in Ruby under the MIT License. Rails is a model–view–controller (MVC) framework, providing default structures for a database, a web service, and web pages. It encourages and facilitates the use of web standards such as JSON or XML for data transfer and HTML, CSS and JavaScript for user interfacing. In addition to MVC, Rails emphasizes the use of other well-known software engineering patterns and paradigms, including convention over configuration (CoC), don't repeat yourself (DRY), and the active record pattern. Ruby on Rails' emergence in 2005 greatly influenced web app development, through innovative features such as seamless database table creations, migrations, and scaffolding of views to enable rapid application development. Ruby on Rails' influence on other web frameworks remains apparent today, with many frameworks in other languages borrowing its ideas, including Django in Pyt ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


JavaServer Faces
Jakarta Faces, formerly Jakarta Server Faces and JavaServer Faces (JSF) is a Java specification for building component-based user interfaces for web applications and was formalized as a standard through the Java Community Process being part of the Java Platform, Enterprise Edition. It is also an MVC web framework that simplifies the construction of user interfaces (UI) for server-based applications by using reusable UI components in a page. JSF 2.x uses Facelets as its default templating system. Users of the software may also choose to employ technologies such as XUL, or Java. JSF 1.x uses JavaServer Pages (JSP) as its default templating system. History In 2001, the original Java Specification Request (JSR) for the technology that ultimately became JavaServer Faces proposed developing a package with the name javax.servlet.ui In June 2001, ''JavaWorld'' would report on Amy Fowler's team's design of "the JavaServer Faces API" (also known as "Moonwalk") as "an application framew ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Web Framework
A web framework (WF) or web application framework (WAF) is a software framework that is designed to support the development of web applications including web services, web resources, and web APIs. Web frameworks provide a standard way to build and deploy web applications on the World Wide Web. Web frameworks aim to automate the overhead associated with common activities performed in web development. For example, many web frameworks provide libraries for database access, templating frameworks, and session management, and they often promote code reuse. Although they often target development of dynamic web sites, they are also applicable to static websites. History As the design of the World Wide Web was not inherently dynamic, early hypertext consisted of hand-coded HTML text files that were published on web servers. Any modifications to published pages needed to be performed by the pages' author. In 1993, the Common Gateway Interface (CGI) standard was introduced for interfa ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Message Authentication Code
In cryptography, a message authentication code (MAC), sometimes known as a ''tag'', is a short piece of information used for authenticating a message. In other words, to confirm that the message came from the stated sender (its authenticity) and has not been changed. The MAC value protects a message's data integrity, as well as its authenticity, by allowing verifiers (who also possess the secret key) to detect any changes to the message content. Terminology The term message integrity code (MIC) is frequently substituted for the term ''MAC'', especially in communications to distinguish it from the use of the latter as ''media access control address'' (''MAC address''). However, some authors use MIC to refer to a message digest, which aims only to uniquely but opaquely identify a single message. RFC 4949 recommends avoiding the term ''message integrity code'' (MIC), and instead using ''checksum'', ''error detection code'', '' hash'', ''keyed hash'', ''message authentication code'', ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]