2023no writeups on CTFtime
HTB University CTF 2023: Brains & Bytes
6 challenges with 7 published solutions between them. CTFtime lists this event but has no writeups filed against it, so it is absent from the index CTFtime feeds. These were found in public repositories instead. Each link is pinned to the commit it was read from.
The event on CTFtimeCryptography4
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
Mayday
1 official solutionMayday Mayday
1 official solutionZombie Rolled
1 official solution
Uncategorised1
The upstream scoreboard did not say, so neither do we.
Fullpwn
1 official solution
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
Windows of Opportunity
1 official solution