Saturday, April 16, 2016

Exploits




Zero-Day Exploits
Called either Day Zero or Zero-Day, it is an exploit that takes advantage of a security vulnerability on the same day that the vulnerability becomes publicly or generally known. Zero-Day exploits are usually posted by well-known hacker groups. Software companies may issue a security bulletin or advisory when the exploit becomes known, but companies may not be able to offer a patch to fix the vulnerability for some time after. 

An exploit (from the same word in the French language, meaning "achievement", or "accomplishment") is a piece of software, a chunk of data, or sequence of commands that takes advantage of a bug, glitch or vulnerability in order to cause unintended or unanticipated behavior to occur on computer software, hardware, or something electronic (usually computerised). This frequently includes such things as gaining control of a computer system or allowing privilege escalation or a denial of service attack.

There are several methods of classifying exploits. The most common is by how the exploit contacts the vulnerable software. A 'remote exploit' works over a network and exploits the security vulnerability without any prior access to the vulnerable system. A 'local exploit' requires prior access to the vulnerable system and usually increases the privileges of the person running the exploit past those granted by the system administrator. Exploits against client applications also exist, usually consisting of modified servers that send an exploit if accessed with client application. Exploits against client applications may also require some interaction with the user and thus may be used in combination with social engineering method. This is the hacker way of getting into computers and websites for stealing data.

In computing, an exploit is an attack on a computer system, especially one that takes advantage of a particular vulnerability that the system offers to intruders. Used as a verb, the term refers to the act of successfully making such an attack.

In Exploit another classification is by the action against vulnerable system: unauthorized data access, arbitrary code execution, denial of service.

Many crackers (or hackers, if you prefer that term) take pride in keeping tabs of such exploits and post their exploits (and discovered vulnerabilities) on a Web site to share with others.

Where an exploit takes advantage of a weakness in an operating system or vended application program, the owners of the system or application issue a "fix" or patch in response. Users of the system or application are responsible for obtaining the patch, which can usually be downloaded from the Web. Failure to install a patch for a given problem exposes the user to a security breach. (However, it can be difficult to keep up with all the required patches.)

Many exploits are designed to provide superuser-level access to a computer system. However, it is also possible to use several exploits, first to gain low-level access, then to escalate privileges repeatedly until one reaches root.

Normally a single exploit can only take advantage of a specific software vulnerability. Often, when an exploit is published, the vulnerability is fixed through a patch and the exploit becomes obsolete for newer versions of the software. This is the reason why some blackhat hackers do not publish their exploits but keep them private to themselves or other crackers. Such exploits are referred to as 'zero day exploits' and to obtain access to such exploits is the primary desire of unskilled attackers, often nicknamed script kiddies.

0 comments:

Post a Comment