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Confused Deputy Problem
In information security, a confused deputy is a computer program that is tricked by another program (with fewer privileges or less rights) into misusing its authority on the system. It is a specific type of privilege escalation. The confused deputy problem is often cited as an example of why capability-based security is important. Capability systems protect against the confused deputy problem, whereas access control list-based systems do not. Example In the original example of a confused deputy, there was a compiler program provided on a commercial timesharing service. Users could run the compiler and optionally specify a filename where it would write debugging output, and the compiler would be able to write to that file if the user had permission to write there. The compiler also collected statistics about language feature usage. Those statistics were stored in a file called "(SYSX)STAT", in the directory "SYSX". To make this possible, the compiler program was given permissi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Information Security
Information security, sometimes shortened to InfoSec, is the practice of protecting information by mitigating information risks. It is part of information risk management. It typically involves preventing or reducing the probability of unauthorized/inappropriate access to data, or the unlawful use, disclosure, disruption, deletion, corruption, modification, inspection, recording, or devaluation of information. It also involves actions intended to reduce the adverse impacts of such incidents. Protected information may take any form, e.g. electronic or physical, tangible (e.g. paperwork) or intangible (e.g. knowledge). Information security's primary focus is the balanced protection of the confidentiality, integrity, and availability of data (also known as the CIA triad) while maintaining a focus on efficient policy implementation, all without hampering organization productivity. This is largely achieved through a structured risk management process that involves: * identifying inform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samy (computer Worm)
Samy (also known as JS.Spacehero) is a cross-site scripting worm (XSS worm) that was designed to propagate across the social networking site MySpace by Samy Kamkar. Within just 20 hours of its October 4, 2005 release, over one million users had run the payload making Samy the fastest-spreading virus of all time. The worm itself was relatively harmless; it carried a payload that would display the string "but most of all, samy is my hero" on a victim's MySpace profile page as well as send Samy a friend request. When a user viewed that profile page, the payload would then be replicated and planted on their own profile page continuing the distribution of the worm. MySpace has since secured its site against the vulnerability. Samy Kamkar, the author of the worm, was raided by the United States Secret Service and Electronic Crimes Task Force in 2006 for releasing the worm. He entered a plea agreement on January 31, 2007 to a felony charge. The action resulted in Kamkar being sentenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Setuid
The Unix Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and ot ... access rights flags setuid and setgid (short for ''set user identity'' and ''set group identity'') allow users to run an executable with the file system permissions of the executable's owner or group respectively and to change behaviour in directories. They are often used to allow users on a computer system to run programs with temporarily elevated privileges in order to perform a specific task. While the assumed user id or group id privileges provided are not always elevated, at a minimum they are specific. The flags setuid and setgid are needed for tasks that require different privileges than what the user is normally granted, such as the ability to alter system files or databases to change their login password. Some of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
File Descriptor
In Unix and Unix-like computer operating systems, a file descriptor (FD, less frequently fildes) is a process-unique identifier (handle) for a file or other input/output resource, such as a pipe or network socket. File descriptors typically have non-negative integer values, with negative values being reserved to indicate "no value" or error conditions. File descriptors are a part of the POSIX API. Each Unix process (except perhaps daemons) should have three standard POSIX file descriptors, corresponding to the three standard streams: Overview In the traditional implementation of Unix, file descriptors index into a per-process maintained by the kernel, that in turn indexes into a system-wide table of files opened by all processes, called the . This table records the ''mode'' with which the file (or other resource) has been opened: for reading, writing, appending, and possibly other modes. It also indexes into a third table called the inode table that describes the actual u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Object-capability Model
The object-capability model is a computer security model. A capability describes a transferable right to perform one (or more) operations on a given object. It can be obtained by the following combination: :* An unforgeable reference (in the sense of object references or protected pointers) that can be sent in messages. :* A message that specifies the operation to be performed. The security model relies on not being able to forge references. :* Objects can interact only by sending messages on references. :* A reference can be obtained by: ::# Initial conditions: In the initial state of the computational world being described, object A may already have a reference to object B. ::# Parenthood: If A creates B, at that moment A obtains the only reference to the newly created B. ::# Endowment: If A creates B, B is born with that subset of A's references with which A chose to endow it. ::# Introduction: If A has references to both B and C, A can send to B a message containing a referen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Personal Firewall
A personal firewall is an application which controls network traffic to and from a computer, permitting or denying communications based on a security policy. Typically it works as an application layer firewall. A personal firewall differs from a conventional firewall in terms of scale. A personal firewall will usually protect only the computer on which it is installed, as compared to a conventional firewall which is normally installed on a designated interface between two or more networks, such as a router or proxy server. Hence, personal firewalls allow a security policy to be defined for individual computers, whereas a conventional firewall controls the policy between the networks that it connects. The per-computer scope of personal firewalls is useful to protect machines that are moved across different networks. For example, a laptop computer may be used on a trusted intranet at a workplace where minimal protection is needed as a conventional firewall is already in place, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FTP Bounce Attack
FTP bounce attack is an exploit of the FTP protocol whereby an attacker is able to use the command to request access to ports indirectly through the use of the victim machine, which serves as a proxy for the request, similar to an Open mail relay using SMTP. This technique can be used to port scan hosts discreetly, and to potentially bypass a network Access-control list to access specific ports that the attacker cannot access through a direct connection, for example with the nmap port scanner. Nmap Scripting Engine documentation Nearly all modern FTP server programs are configured by default to refuse commands that would connect to any host but the originating host, thwarting FTP bounce attacks. See also * ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clickjacking
Clickjacking (classified as a user interface redress attack or UI redressing) is a malicious technique of tricking a user into clicking on something different from what the user perceives, thus potentially revealing confidential information or allowing others to take control of their computer while clicking on seemingly innocuous objects, including web pages. Clickjacking is an instance of the confused deputy problem, wherein a computer is tricked into misusing its authority.The Confused Deputy rides again! Tyler Close, October 2008 History In 2002, it had been noted that it was possible to load a transparent layer over a web page and have the user's input affect the transparent layer without the user noticing. H ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cross-site Scripting
Cross-site scripting (XSS) is a type of security vulnerability that can be found in some web applications. XSS attacks enable attackers to inject client-side scripts into web pages viewed by other users. A cross-site scripting vulnerability may be used by attackers to bypass access controls such as the same-origin policy. Cross-site scripting carried out on websites accounted for roughly 84% of all security vulnerabilities documented by Symantec up until 2007.During the second half of 2007, 11,253 site-specific cross-site vulnerabilities were documented by XSSed, compared to 2,134 "traditional" vulnerabilities documented by Symantec, in XSS effects vary in range from petty nuisance to significant security risk, depending on the sensitivity of the data handled by the vulnerable site and the nature of any security mitigation implemented by the site's owner network. Background Security on the web depends on a variety of mechanisms, including an underlying concept of trust know ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Web Browser
A web browser is application software for accessing websites. When a user requests a web page from a particular website, the browser retrieves its files from a web server and then displays the page on the user's screen. Browsers are used on a range of devices, including desktops, laptops, tablets, and smartphones. In 2020, an estimated 4.9 billion people used a browser. The most used browser is Google Chrome, with a 65% global market share on all devices, followed by Safari with 18%. A web browser is not the same thing as a search engine, though the two are often confused. A search engine is a website that provides links to other websites. However, to connect to a website's server and display its web pages, a user must have a web browser installed. In some technical contexts, browsers are referred to as user agents. Function The purpose of a web browser is to fetch content from the World Wide Web or from local storage and display it on a user's device. This process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Program
A computer program is a sequence or set of instructions in a programming language for a computer to execute. Computer programs are one component of software, which also includes documentation and other intangible components. A computer program in its human-readable form is called source code. Source code needs another computer program to execute because computers can only execute their native machine instructions. Therefore, source code may be translated to machine instructions using the language's compiler. ( Assembly language programs are translated using an assembler.) The resulting file is called an executable. Alternatively, source code may execute within the language's interpreter. If the executable is requested for execution, then the operating system loads it into memory and starts a process. The central processing unit will soon switch to this process so it can fetch, decode, and then execute each machine instruction. If the source code is requested for execution, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cross-site Request Forgery
Cross-site request forgery, also known as one-click attack or session riding and abbreviated as CSRF (sometimes pronounced ''sea-surf'') or XSRF, is a type of malicious exploit of a website or web application where unauthorized commands are submitted from a user that the web application trusts. There are many ways in which a malicious website can transmit such commands; specially-crafted image tags, hidden forms, and JavaScript fetch or XMLHttpRequests, for example, can all work without the user's interaction or even knowledge. Unlike cross-site scripting (XSS), which exploits the trust a user has for a particular site, CSRF exploits the trust that a site has in a user's browser. In a CSRF attack, an innocent end user is tricked by an attacker into submitting a web request that they did not intend. This may cause actions to be performed on the website that can include inadvertent client or server data leakage, change of session state, or manipulation of an end user's account. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
