Challenges → Cryptography

Weak RSA Key

Medium 200 pts 🚩 27 solves ⏱ Avg. time to solve: 62d 13h

Challenge Question

During a routine key-rotation review, this intercepted RSA public key stood out to the crypto team. Something about how it was generated cut corners, leaving its modulus far weaker than it should be. Factor it, rebuild the private key, and decrypt the intercepted ciphertext to recover the flag.
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Details

  • CategoryCryptography
  • Authortark
  • AddedJul 4, 2026
  • Avg. Time to Solve62d 13h
  • First Blood🩸 zsimon

Recent Solvers

  • BlackCipherX 5d ago
  • piyush69 5d ago
  • Max Oct 18, 2026
  • Nyx_Nightmare Oct 12, 2026
  • keybe456 Oct 12, 2026
  • amalmj Oct 7, 2026
  • durga Oct 6, 2026
  • V1XU Oct 3, 2026
  • ajay Oct 2, 2026
  • Jessu Sep 21, 2026
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