2021weight 18.71The Cyber Grabs
Cyber Grabs CTF 0x02
3 challenges with 8 published community solutions between them. Solution links go to CTFtime’s task page, which aggregates every writeup for a challenge - individual blog posts rot, the aggregator does not.
Full task list on CTFtimeCryptography2
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
- crypto
Same technique in picoCTF: StegoRSA, Timestamped Secrets, AES-ABC
- crypto
Same technique in picoCTF: StegoRSA, Timestamped Secrets, AES-ABC
Forensics1
Recover something from a file, a capture, or a disk image - often from a part of it the format says is unused.
Solve it with:File type identifier by magic bytesMagic byte and file signature tablePCAP analyzer for CTF network forensicsEXIF metadata viewerLearn: File forensics and carvingLearn: Network forensics
- forensics
Same technique in picoCTF: FindAndOpen, c0rrupt, extensions