2021from the authors’ own sites
HKCERT CTF Postmortem I 2021
1 challenge with 1 published solution between them. The writeups for this event were found on the authors’ own sites.
Where these writeups liveCryptography1
Recover a plaintext or a key from something that was supposed to protect it. In practice: identify the scheme, find the parameter the author got wrong, exploit it.
Solve it with:Cipher identifier and automatic decoderVigenere cipher solver with automatic key recoveryRSA decryption and attack runnerWiener’s attack on small RSA private exponentsIn-browser hash cracker with rule transformsLearn: Classical ciphers and frequency analysisLearn: RSA and the parameters that break it
Easier Crypto
1 official solutionAlso written up in: mystiz.hk