I have ten piece of ciphered texts. I know that they ciphered with a same-length key. Any idea how I can decrypt the ciphertexts? What kind of algorithms should I use? What are the points of taking care of 'XORing' these texts with each other and space character? (text ciphered with the asymmetric key) should we use the frequency analysis?

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    $\begingroup$ Welcome to Cryptography Stack Exchange. Your question is missing some details – which encrytion algorithm is in use? If it is some misused one-time-pad, look other questions with that tag. $\endgroup$ Commented May 10, 2014 at 12:12
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    $\begingroup$ Didn't know Crypto I was running again at Coursera... $\endgroup$
    – Maarten Bodewes
    Commented May 10, 2014 at 18:18
  • $\begingroup$ first of all i am student in cs and got this take-home. As i said have only ten short ciphered text and also information of those ciphered with the same key...(XOR cipher and a key). That's all. $\endgroup$
    – firehorse
    Commented May 10, 2014 at 19:29
  • $\begingroup$ You are looking for how to attack one time pad reuse. There is a lot of information already on this site for that. Have a look around. $\endgroup$
    – mikeazo
    Commented May 11, 2014 at 3:31
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    $\begingroup$ See also: How does one attack a two-time pad (i.e. one time pad with key reuse)? $\endgroup$ Commented May 11, 2014 at 12:57


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