Birthday attack definition
A birthday attack is an attack that occurs when someone exploits the mathematics behind the birthday problem in probability theory to launch a cryptographic attack. The birthday problem states that in a group of 23 people, there’s a 50% chance that at least two will have the same birthday. This probability increases rapidly as the group size gets bigger. For instance, in a group of 50 people, the likelihood is already over 97%.
During a birthday attack, the attacker tries to find two different input messages that produce the same hash value, called a collision. By finding a collision, the attacker can deceive a system into believing that two other notes are identical. For instance, they can forge a digital signature or crack a password hash.
Birthday attacks pose a significant security threat because they are relatively easy to execute and can undermine various cryptographic systems.
Protecting against birthday attacks
- Use robust cryptographic algorithms and implement them correctly.
- Employ strong encryption.
- Regularly update hash functions.
- Use salted hashes.
- Implement message authentication codes (MACs).
- Practice rigorous key management.
- Maintain vigilant system monitoring.
- Conduct regular security audits.
- Promote security awareness and training.