Editing Logic bomb (section)

{{Short description|Intentional delayed sabotage of a computer program with activation subject to conditions}}
{{Use dmy dates|date=March 2014}}
A '''logic bomb''' is a piece of [[source code|code]] intentionally inserted into a [[software]] system that will set off a malicious function when specified conditions are met. For example, a programmer may hide a piece of code that starts deleting [[computer file|files]] (such as a salary [[database trigger]]), should they ever be terminated from the company.

Software that is inherently malicious, such as [[computer virus|viruses]] and [[computer worm|worms]], often contain logic bombs that execute a certain [[Payload (software)|payload]] at a pre-defined time or when some other condition is met. This technique can be used by a virus or worm to gain momentum and spread before being noticed. Some viruses attack their host systems on specific dates, such as [[Friday the 13th]] or [[April Fools' Day]]. [[Trojan horse (computing)|Trojans]] and other [[computer viruses]] that activate on certain dates are often called "[[time bomb (software)|time bombs]]".

To be considered a logic bomb, the payload should be unwanted and unknown to the user of the software. As an example, trial programs with code that [[Crippleware|disables certain functionality]] after a set time are not normally regarded as logic bombs.