Challenge list
Network SecurityLevel 4★★★★☆Network Analysis - Rebuilding Chunked gzip HTTP from TCP
capture.pcap records two HTTP exchanges over one TCP connection. The server's segments are reordered and some are…
Network SecurityLevel 4★★★★☆Network Analysis - TCP Retransmission Covert Channel
capture.pcap contains TCP retransmissions with duplicate sequence numbers. Extract retransmissions whose payload…
CryptographyLevel 4★★★★☆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…
CryptographyLevel 4★★★★☆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…
CryptographyLevel 4★★★★☆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} =…