In computer security, capture the flag (CTF) is an information warfare game. Each team is given a machine (or small network) to defend on an isolated network. Teams are scored on both their success in defending their assigned machine and on their success in attacking other team's machines. Depending on the nature of the particular CTF game, teams may either be attempting to take an opponent's flag from their machine or teams may be attempting to plant their own flag on their opponent's machine. ...

See also:

Capture the flag, Capture the flag - Software/games, Capture the flag - Computer security, Capture the flag - Urban Gaming

Read more here: » Capture the flag: Encyclopedia II - Capture the flag - Computer security

See also:

Shibboleth, Shibboleth - Modern usage, Shibboleth - Some shibboleths, Shibboleth - Shibboleths used in war, Shibboleth - Humorous shibboleths, Shibboleth - Shibboleths in fiction, Shibboleth - Grammatical shibboleths, Shibboleth - Other shibboleths, Shibboleth - Computer security

Read more here: » Shibboleth: Encyclopedia II - Shibboleth - Computer security

Computer security is a field of computer science concerned with the control of risks related to computer use. The means traditionally taken to realize this objective is to attempt to create a secure computing platform, designed so that agents (users or programs) can only perform actions that have been allowed. This involves specifying and implementing a security policy. The actions in question can be reduced to operations of access, modification and deletion. Computer security can be seen as a subfield of security engine ...

Including:

Computer security - Computer security by design Computer security - Early history of security by design Computer security - Techniques for creating secure systems Computer security - Capabilities vs. ACLs Computer security - Other uses of the term trusted Computer security - Notable persons in computer security

Read more here: » Computer security: Encyclopedia - Computer security

The following techniques can be used in engineering secure systems. These techniques, whilst useful, do not of themselves ensure security. One security maxim is "a security system is no stronger than its weakest link" Automated theorem proving and other verification tools can enable critical algorithms and code used in secure systems to be mathematically proven to meet their specifications. Thus simple microkernels can be written so that we can be sure they don't contain any bugs: eg EROS[1] and Coyotos[2]. A b ...

See also:

Computer security, Computer security - Computer security by design, Computer security - Early history of security by design, Computer security - Techniques for creating secure systems, Computer security - Capabilities vs. ACLs, Computer security - Other uses of the term trusted, Computer security - Notable persons in computer security

Read more here: » Computer security: Encyclopedia II - Computer security - Techniques for creating secure systems

In security engineering and computer security, authorization, is a part of the operating system that protects computer resources by only allowing those resources to be used by resource consumers that have been granted authority to use them. Resources include individual files or items data, computer programs, computer devices and functionality provided by computer applications. Examples of consumers are computer users, computer programs and other devices on the computer. The authorization process is used to decide if person, program or device X is allowed ...

Including:

Authorization - Authorization in Public Policy

Read more here: » Authorization: Encyclopedia - Authorization

Anonymous key exchange, like Diffie-Hellman, does not provide authentication of the parties, and is thus vulnerable to man in the middle (MITM) attack. A wide variety of cryptographic authentication schemes and protocols have been developed to provide authenticated key agreement to prevent man-in-the-middle and related attacks. These methods generally mathematically bind the agreed key to other agreed-upon data, such as: Public/private key pairs Shared secret keys Passwords See also:

Key-agreement protocol, Key-agreement protocol - Exponential key exchange, Key-agreement protocol - Authentication, Key-agreement protocol - Public keys, Key-agreement protocol - Hybrid systems, Key-agreement protocol - Passwords, Key-agreement protocol - Other tricks, Key-agreement protocol - Shared secret keys

Read more here: » Key-agreement protocol: Encyclopedia II - Key-agreement protocol - Authentication

Almost every IRC client offers some kind of flood protection. These protections are based on the built-in "ignore" feature, which means that a given incoming message, CTCP, invitation, etc. will be blocked if the sender's hostmask matches any of the masks are defined in the ignore list. This is useful as few IRC networks implement the 'silence' command to reject messages by the server. In other words, every message will be posted to the correspondent user, whether it is a normal message or its content is intentionally malicious. IRC ...

See also:

IRC floods, IRC floods - Types of floods, IRC floods - Clones, IRC floods - Protection, IRC floods - Flood protection in mIRC, IRC floods - Firewalls and floods

Read more here: » IRC floods: Encyclopedia II - IRC floods - Protection

Of course, abusers do not flood from their own nicknames, because of the following reasons: they can easily be K-Lined by administrators ('ServerOPs' or 'SOPs'), banned from channels by operators ('ChanOPs' or 'OPs'), from one user the flood is often not effective (The limits apply to the attacker too). Instead clones are used, which are script or program controlled clients, primary designed to abuse others. Thanks to this, it's pretty easy to attack a user by many clones at the same time. Generally, the more clones an abuser has, the bigger t ...

See also:

IRC floods, IRC floods - Types of floods, IRC floods - Clones, IRC floods - Protection, IRC floods - Flood protection in mIRC, IRC floods - Firewalls and floods

Read more here: » IRC floods: Encyclopedia II - IRC floods - Clones

The MITM attack may include one or more of: eavesdropping, including traffic analysis and possibly a known plaintext attack chosen ciphertext attack, depending on what the receiver does with a message that it decrypts substitution attack replay attacks denial of service attack. The attacker may for instance jam all communications before attacking one of the parties. The defense is for both parties to periodically send authenticated status messages and to treat their disappearance with paranoia. MITM is typically used to refer to active ma ...

See also:

Man-in-the-middle attack, Man-in-the-middle attack - The need for an additional transfer over a secure channel, Man-in-the-middle attack - Possible subattacks, Man-in-the-middle attack - Public-key cryptography example using public-key encryption, Man-in-the-middle attack - Defenses against the attack, Man-in-the-middle attack - Beyond cryptography, Man-in-the-middle attack - External link

Read more here: » Man-in-the-middle attack: Encyclopedia II - Man-in-the-middle attack - Possible subattacks

A buffer overflow occurs when data written to a buffer, due to insufficient bounds checking, corrupts data values in memory addresses adjacent to the allocated buffer. Most commonly this occurs when copying strings of characters from one buffer to another. Buffer overflow - Basic example. In the following example, a program has defined two data items which are adjacent in memory: an 8-byte-long string buffer, A, and a two-byte integer, B. Initially, A contains nothing but zero bytes, a ...

See also:

Buffer overflow, Buffer overflow - Technical description, Buffer overflow - Basic example, Buffer overflow - Buffer overflows on the stack, Buffer overflow - Exploits, Buffer overflow - Example, Buffer overflow - Protection against buffer overflows, Buffer overflow - Choice of programming language, Buffer overflow - Use of safe libraries, Buffer overflow - Stack-smashing protection, Buffer overflow - Executable space protection, Buffer overflow - Address Space Layout Randomization, Buffer overflow - Deep Packet Inspection, Buffer overflow - History

Read more here: » Buffer overflow: Encyclopedia II - Buffer overflow - Technical description

A shellcode may be used as an exploit payload, providing a cracker with command line access to a computer system with the privileges of the process that has been exploited. To avoid detection by anti-intrusion measures and to store more than one string, crackers often make use of self-decrypting code, polymorphic code and alphanumeric code. Shellcodes can be stored in a process' memory space and subsequently executed as a result of the attacker gaining control of the program counter using vulnerabilities such as stack and heap-based b ...

See also:

Shellcode, Shellcode - Shellcode execution strategy, Shellcode - Shellcode communication methods, Shellcode - Shellcode mitigation strategies

Read more here: » Shellcode: Encyclopedia II - Shellcode - Shellcode execution strategy

BSD is a family of free, open source Unix variants derived from a codebase originating at the University of California, Berkeley. All derived BSD operating systems are released under the terms of a BSD-style license. There are several BSD variants, with only one being heavily focused on security. Security focused operating system - OpenBSD. OpenBSD is an open source BSD operating system that is known to be concerned heavily with security. The project has completed rigorous manual sweeps of the code to addr ...

See also:

Security focused operating system, Security focused operating system - BSD, Security focused operating system - OpenBSD, Security focused operating system - TrustedBSD, Security focused operating system - Linux, Security focused operating system - Adamantix, Security focused operating system - Annvix, Security focused operating system - Hardened Gentoo, Security focused operating system - Immunix, Security focused operating system - Solaris, Security focused operating system - Trusted Solaris

Read more here: » Security focused operating system: Encyclopedia II - Security focused operating system - BSD

Windows-based computers can rapidly accumulate a great many spyware components. Users frequently notice unwanted behavior and degradation of system performance. A spyware infestation can create significant unwanted CPU activity, disk usage, and network traffic -- slowing down legitimate uses of these resources. Stability issues -- application or system crashes -- are also common. Spyware which interferes with the networking software commo ...

See also:

Spyware, Spyware - History and development, Spyware - Spyware adware and tracking, Spyware - Routes of infection, Spyware - Effects and behaviors, Spyware - Advertisements, Spyware - Stealware and affiliate fraud, Spyware - Identity theft and fraud, Spyware - Digital rights management, Spyware - Spyware and cookies, Spyware - Typical examples of spyware, Spyware - User consent and legality, Spyware - Remedies and prevention, Spyware - Anti-spyware programs, Spyware - Security practices, Spyware - Notable programs distributed with spyware, Spyware - Notable programs formerly distributed with spyware

Read more here: » Spyware: Encyclopedia II - Spyware - Effects and behaviors

Spyware rarely comes alone: an affected computer can rapidly become infected with large numbers of spyware components. Users frequently notice unwanted behavior and degradation of system performance. A spyware infestation can create significant unwanted CPU activity, disk usage, and network traffic — slowing down legitimate uses of these resources. Stability issues — application or system crashes — are also common. Spyware which interferes with the networking software commo ...

See also:

Spyware, Spyware - History and development, Spyware - Spyware adware and tracking, Spyware - Routes of infection, Spyware - Effects and behaviors, Spyware - Advertisements, Spyware - Stealware and affiliate fraud, Spyware - Identity theft and fraud, Spyware - Digital rights management, Spyware - Spyware and cookies, Spyware - Typical examples of spyware, Spyware - User consent and legality, Spyware - Remedies and prevention, Spyware - Anti-spyware programs, Spyware - Security practices, Spyware - Notable programs distributed with spyware, Spyware - Notable programs formerly distributed with spyware

Read more here: » Spyware: Encyclopedia II - Spyware - Effects and behaviors

SE Linux is available with commercial support as part of Red Hat Enterprise Linux version 4. In community supported Linux distributions it has been available in Fedora Core since version 2, it is part of Hardened Gentoo, and work is proceeding on making it part of Debian[1], SUSE[2], Slackware[3], Ubuntu[4], and others. ...

See also:

Security-Enhanced Linux, Security-Enhanced Linux - Features, Security-Enhanced Linux - Implementations, Security-Enhanced Linux - Quotes

Read more here: » Security-Enhanced Linux: Encyclopedia II - Security-Enhanced Linux - Implementations

Most current real-world computer security efforts focus on external threats, and generally treat the computer system itself as a trusted system. Some knowledgeable observers consider this to be a disastrous mistake, and point out that this distinction is the cause of much of the insecurity of current computer systems - once an attacker has subverted one part of a system without fine-grained security, he or she usually has access to most or all of the features of that system. Because computer systems are very complex, and cannot be guaranteed to be free ...

See also:

Computer insecurity, Computer insecurity - Security and systems design, Computer insecurity - Financial cost, Computer insecurity - Reasons, Computer insecurity - Vulnerabilities, Computer insecurity - Code exploits, Computer insecurity - Eavesdropping, Computer insecurity - Social engineering and human error, Computer insecurity - Denial of service attacks, Computer insecurity - Indirect attacks, Computer insecurity - Backdoors, Computer insecurity - Direct access attacks, Computer insecurity - Reducing vulnerabilities, Computer insecurity - Security measures, Computer insecurity - Difficulty with response, Computer insecurity - Further reading

Read more here: » Computer insecurity: Encyclopedia II - Computer insecurity - Security and systems design

A canary trap is a method for exposing an information leak, that involves giving different versions of sensitive information to each of a group of suspects and seeing which version gets leaked. The term was coined by Tom Clancy in his novel Patriot Games. The hero, Jack Ryan, describes the technique he devised for identifying the sources of leaked classified documents: Each summary paragraph has six different versions, and the mixture of those paragraphs is unique to each numbered copy of the paper. There ar ...

Including:

Canary trap - External link

Read more here: » Canary trap: Encyclopedia - Canary trap

War dialing or wardialing was a technique in the 1980s and '90s by which a computer would repeatedly dial a number (usually to a crowded modem pool) in an attempt to gain access immediately after another user had hung up. The term (and the technique) pre-date the movie WarGames by several years. However, the popularity of the film among computer enthusiasts led to the term being commonly used for what is more precisely known as demon dialing, which figures prominently in the movie. The expansion of accessible inte ...

Including:

War dialing - External link

Read more here: » War dialing: Encyclopedia - War dialing

Capture the flag is a traditional outdoor game often played by children where two teams have a flag each and the objective is to capture the other team's flag, located at the team's "base", and bring it back to their own base. It is also a popular paintball game. Capture the flag - Software/games. In 1995, Richard Carr released a MS-DOS based game called Capture the Flag. It is a turn based strategy game with real time network / modem play (or play-by-mail) based around the traditional outdoo ...

Including:

Capture the flag - Software/games Capture the flag - Computer security Capture the flag - Urban Gaming

Read more here: » Capture the flag: Encyclopedia - Capture the flag

Various techniques have been used to detect or prevent buffer overflows, with various tradeoffs. The most reliable way to avoid or prevent buffer overflows is to use automatic protection at the language level. This sort of protection, however, cannot be applied to legacy code, and often technical, business, or cultural constraints call for a vulnerable language. The following sections describe the choices and implementations available. ...

See also:

Buffer overflow, Buffer overflow - Technical description, Buffer overflow - Basic example, Buffer overflow - Buffer overflows on the stack, Buffer overflow - Exploits, Buffer overflow - Example, Buffer overflow - Protection against buffer overflows, Buffer overflow - Choice of programming language, Buffer overflow - Use of safe libraries, Buffer overflow - Stack-smashing protection, Buffer overflow - Executable space protection, Buffer overflow - Address Space Layout Randomization, Buffer overflow - Deep Packet Inspection, Buffer overflow - History

Read more here: » Buffer overflow: Encyclopedia II - Buffer overflow - Protection against buffer overflows