Warning!

• When we gave this talk in 2000 we said:

• • No two documents have yet been discovered which have the same MD5 digest!
  • No feasible method to create any document that has a given MD5 digest.

• The first statement is now categorically untrue.

• The second is now less true than it once was.

• SHA1 is now looking a little weak as well.

• The implication is clear, you need to periodically evaluate the threats to cryptographic systems based on current knowledge.