Quantum Cryptography Challenge

Decrypt quantum-secure ciphers by exploiting classical vulnerabilities. Master RSA, AES, XOR, and timing attacks in a professional security environment.

Difficulty
Medium-Hard
Points
500
Vulnerabilities
5+
Time
30-45 min
API Explorer CLI Interface Exploit Script Guide

Cryptography Mastery Path

Stage 0 of 6 0% Complete
1
Weak RSA Factorization
2
AES-ECB Pattern Leakage
3
CBC Padding Oracle
4
XOR Stream Cipher Reuse
5
HMAC Timing Attack
6
Final Flag Assembly
Stage 1: Weak RSA Factorization
Next: ECB Pattern Analysis
+50 Points
Challenge Ciphertext
zk7Sjr8JHOMN+a+of7czd1AbOqJBIeE6qoQNqsB0wK2PXBGWT0SZjbnOCrfMqt/ikHPm8DJPBpj9G1+QEH/Rufo77pIQR/nZah+a0AxKBazmokUVDuo9CAZu3bHJZlki+03eN+DgbrHq8tv96ORL1AW78+b43pnJH+solNuZwfQ=

Recommended Tool

yafu, msieve, RsaCtfTool

Exploit Command

python3 -c "from Crypto.PublicKey import RSA; import gmpy2; n = MODULUS; e = 65537; # Factor n"

Vulnerability Hint

1024-bit RSA is weak. Factor using yafu: yafu "factor(@)" -batchfile <(echo "MODULUS_HERE" )

Challenge Details

  • Category Real Cryptography
  • Difficulty Medium-Hard
  • CVSS Score 8.5 (High)
  • Attack Vectors 5
  • Challenge ID f5ce021b3fcd

Cryptographic Vulnerabilities

  • Weak RSA (1024-bit, factorable)
  • AES-ECB mode (pattern leakage)
  • CBC padding oracle (POODLE)
  • XOR key reuse (stream cipher)
  • Timing attack (strcmp vs hash_equals)
  • IV reuse in CBC mode

API Reference

GET
/crypto1/?api&action=get_challenge
GET
/crypto1/?api&action=decrypt&cipher=[base64]
GET
/crypto1/?api&action=verify&token=[token]
GET
/crypto1/?api&action=attack&type=[type]

Learning Objectives

RSA Cryptanalysis
Block Cipher Modes
Timing Attacks
Secure Implementation

Cyber Fortress CTF • Quantum Cryptography Challenge • COMP50003 Cyber Security

CTF Dashboard CLI Exploitation Security Guide Reset Challenge

© 2026 Cyber Security Program. This environment contains intentionally vulnerable software for educational purposes only.
Use only in controlled, authorized environments. Never test systems without explicit permission.