2021from public repositories
Anon CTF 2021
7 challenges with 7 published solutions between them. CTFtime has no listing for this event at all, so nothing built on CTFtime can show what it was made of. These writeups were found in public repositories instead. Each link is pinned to the commit it was read from.
Where these writeups liveUncategorised3
The upstream scoreboard did not say, so neither do we.
Buffer Overflow
1 official solutionImitation
1 official solution
Cryptography3
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
Monoalphabetic Substitution
1 official solutionPassword Encrypter
1 official solution
Steganography1
Find the payload hidden inside a carrier that looks ordinary. Bit planes, appended data, metadata, and audio spectrograms.
Solve it with:LSB steganography extractorPNG chunk analyzerAudio spectrogram and SSTV decoderZero-width character and text steganography decoderLearn: Steganography
Back to Basics
1 official solution