Timing attack

In cryptography, a timing attack is a side channel attack in which the attacker attempts to compromise a cryptosystem by analyzing the time taken to execute cryptographic algorithms. Every logical operation in a computer takes time to execute, and the time can differ based on the input; with precise measurements of the time for each operation, an attacker can work backwards to the input.

Information can leak from a system through measurement of the time it takes to respond to certain queries. How much such information can help an attacker depends on many variables: crypto system design, the CPU running the system, the algorithms used, assorted implementation details, timing attack countermeasures, the accuracy of the timing measurements, etc.

Timing attacks are often overlooked in the design phase because they are so dependent on the implementation.

Concept

A timing attack is an example of an attack that exploits the data-dependent behavioral characteristics of the implementation of an algorithm rather than the mathematical properties of the algorithm itself.