2021weight 30.75Square
Block CTF 2021
2 challenges with 3 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 CTFtimeWeb1
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: Web attacks and session tokens
- web
Same technique in picoCTF: Client-side-again, dont-use-client-side, Irish-Name-Repo 3
Reverse engineering1
Work out what a compiled program does without its source, then work backwards from the check to the input that passes it.
Solve it with:Strings extractor for binaries and blobsWebAssembly disassemblerJava .class disassemblerPython .pyc bytecode disassemblerLearn: Binary exploitation
- rev
Same technique in picoCTF: Secure Password Database, vault-door-6, OTP Implementation