2025from public repositories
ASCIS Final 2025
3 challenges with 5 published solutions between them. The writeups for this event were found in public repositories. Each link is pinned to the commit it was read from.
Where these writeups liveReverse 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
Analyze Hashes
1 official solutionAlso written up in: SandWithCheese/ctf-writeups
Uncategorised1
The upstream scoreboard did not say, so neither do we.
Also written up in: SandWithCheese/ctf-writeups
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
Also written up in: SandWithCheese/ctf-writeups, SandWithCheese/ctf-writeups, SandWithCheese/ctf-writeups