What is the Process to Decrypt Ciphertexts Encrypted with the Same One Time Pad?

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SUMMARY

The discussion revolves around decrypting two ciphertexts encrypted with the same One Time Pad (OTP). Both ciphertexts share identical headers and consist of 100 characters, suggesting potential padding. The user has attempted to XOR the ciphertexts but is uncertain about the subsequent steps. A hint regarding the timestamps indicates that the times correspond to prime numbers, which may relate to RSA encryption principles.

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  • Understanding of One Time Pad encryption and its properties
  • Familiarity with XOR operations in cryptography
  • Knowledge of prime numbers and their significance in encryption algorithms
  • Basic skills in analyzing ciphertext structures and patterns
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  • Research the implications of using the same One Time Pad for multiple messages
  • Learn about XOR decryption techniques and their applications in cryptanalysis
  • Investigate the relationship between prime numbers and RSA encryption
  • Explore padding schemes used in cryptographic messages
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Cryptographers, security analysts, and students of cryptography looking to deepen their understanding of One Time Pad vulnerabilities and decryption techniques.

everQuest
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Hi everyone

I've been given a challenge and i was wondering if you guys could shed some light on it...

i have been given two ciphertexts that have been encrypted with the same one time pad... the ciphertexts start the same (message header), but I am not given any more information about it...

the ciphertexts are split up into the same number of blocks so i think padding may have been used...

im assuming xor, they haven't given us any information (im also assuming one time pad used twice, because of the message headers)...

heres the cipher texts so you see what i mean

3:17am :
UWCHR IFLFK AFFTG WVOOM SZYUJ
QVGBR LZFSC CWAXZ KCIUE KDZEA
RIAAY HHJTN DLCWV CIIJE WARON
JEDZO IKFNM AFJJL FVSZE MEFOM

4:29am :
UWCHR IFLFK AFFTG WVOHI LDOQX
NYQUE PHRSC BDIBB FHMTI VKVOA
RHMTQ EZACG INLDH ALTHI ISGHV
AGSPI WPJML BSICH BKZNX TAFGE

so they start the same, each cipher text has exactly 100 characters in it, I've xor'd the ciphertexts but I am not quite sure what to do next.

Also there is a hint from one guy who has solved this cipher:

just look at the time at which the ciphertext was sent: 3:17( = 3x60+17 = 197) and 4:29 ( = 4x60 + 29 = 269), both of these are primes.

any help would be great!
 
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Two primes are used in the RSA algorithm, so that's my guess.
 

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