Consider the one time pad with messages and keystreams in binary strings. Suppose that the system is used erroneously, so that two messages have been encrypted using the same key. What information can an adversary that gets the two chipertexts deduce about the plaintexts?

  • 2
    $\begingroup$ This looks very much like a homework assignment. Please read first part of my answer here: crypto.stackexchange.com/questions/33673/… to understand the theory that will allow you to answer your question. $\endgroup$ – Filip Franik Feb 28 '18 at 8:41
  • $\begingroup$ If the two messages happen to be the same you can deduce the length of the plain text, which you might not have known before depending on padding. $\endgroup$ – daniel Feb 28 '18 at 11:35

Your Answer

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.

Browse other questions tagged or ask your own question.