What are the limits of hash functions?

What are the limits of hash functions?

Hash functions are designed to take an input and produce a fixed-size string of bytes. However, they have limitations such as collision resistance, pre-image resistance, and the inability to reverse the hash back to the original input.

Can you explain what collision resistance means?

Collision resistance means that it should be computationally infeasible to find two different inputs that produce the same hash output. This is crucial for ensuring the integrity of data.

What happens if a hash function is not collision-resistant?

If a hash function is not collision-resistant, it can lead to vulnerabilities where two different inputs can produce the same hash, potentially allowing for data tampering or fraud.

Are there any real-world examples of hash function failures?

Yes, one notable example is the MD5 hash function, which has known vulnerabilities that allow for collision attacks, making it unsuitable for security purposes.