Challenge list
Encrypted Communication - GPG Public Key Cryptography
Practice GnuPG decryption. Import every private key under `/challenge/keys/` and decrypt each ciphertext under…
Cryptanalysis - DSA Nonce Reuse Key Recovery
/challenge/signatures.json, created with fresh keys at every start, holds the DSA public parameters (p of 1024 bits, q…
Cryptanalysis - Wiener's Attack on RSA
An embedded-device team made the RSA private exponent d very small to speed up decryption. The public exponent e in…
Cryptanalysis - Recovering an LCG's Hidden Parameters
A service generated both session tokens and an encryption keystream from a linear congruential generator x_{k+1} =…
Vulnerability Scanning - Advanced Nmap NSE
The results of running `nmap -sV -sC --script vuln` against the internal subnet `10.66.13.0/24` are in…
Static Analysis - Code Vulnerability Scanning
The Python source of an internal notes app is in `/challenge/src/`. The nine lines flagged by an earlier…