# Algorithmic complexity attack

An algorithmic complexity attack is a form of computer attack that exploits known cases in which an algorithm used in a piece of software will exhibit worst case behavior. This type of attack can be used to achieve a denial-of-service.

## Examples

• Quicksort - popular and fast in-place sorting algorithm, running ${\displaystyle O(n\log n)}$ on average, but having ${\displaystyle O(n^{2})}$ behaviour if implemented naïvely.