2020from the authors’ own sites
CTF TGHACK 2020
3 challenges with 3 published solutions between them. The writeups for this event were found on the authors’ own sites.
Where these writeups liveWeb1
Reach data or functionality the application meant to keep from you - through its inputs, its tokens, or its trust in the client.
Solve it with:JWT decoder and signature verifierJWT alg=none bypass generatorWeb attack payload catalogJWT secret brute forceLearn: Sessions, tokens and access control
– Exfiltration 150pt
1 official solutionAlso written up in: hell38vn.wordpress.com
Misc1
Everything that fits no other box: esolangs, puzzles, scripting exercises, and the jail escapes that have not yet earned their own category.
Solve it with:Brainfuck and esolang decoderCipher identifier and automatic decoderRegex tester with match offsets and capture groupsLearn: Recognising encodings
– Poke 142pt
1 official solutionAlso written up in: hell38vn.wordpress.com
Cryptography1
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
– The Message 137pt
1 official solutionAlso written up in: hell38vn.wordpress.com