Derek wants to conduct a birthday attack against a digital signature. Which of the following best describes the process he would need to take to achieve his goal?
Answer Options
He needs to prepare both a correct and a malicious document and find ways to modify the correct document until its encryption matches the malicious document.
He needs to make sure all dates match in both a correct and a malicious document.
He needs to ensure that the file length and creation date match for both a correct document and a malicious document.
He needs to prepare both a correct and a malicious document, then find ways to modify the malicious document until its hash matches the hash of the correct document.
Correct Answer: D
Explanation
Derek knows that attacking a digital signature requires that hashes match for both an original document and a malicious document. He will modify the malicious document until he finds a way to convey the changes he needs while retaining the matching hash. This type of attack is why hashing algorithms needs to be resistant to birthday attacks.