2025from public repositories
Intersec HCS 2025
30 challenges with 48 published solutions between them. CTFtime has no listing for this event at all, so nothing built on CTFtime can show what it was made of. These writeups were found in public repositories instead. Each link is pinned to the commit it was read from.
Where these writeups liveUncategorised28
The upstream scoreboard did not say, so neither do we.
Atadatem
3 official solutionsBlind File
3 official solutionsGuessr1
3 official solutionsGuessr2
3 official solutionsBased
2 official solutionsGuessr3
2 official solutionsI Forgot Something
2 official solutionsJinja Ninja
2 official solutionsLeFI Gimang
2 official solutionsNothing
2 official solutionsSquare
2 official solutionsStrings
2 official solutionsToggle
2 official solutionsCosmic Tongue
1 official solutionDay 1
1 official solutionElefay
1 official solutionHexahue Bergerak
1 official solutionLockpicking
1 official solutionMulti Redact
1 official solutionMy Networ(th)k
1 official solutionSnakev3
1 official solutionsPYware
1 official solutionThree Umazing Things
1 official solutionTinggal Run
1 official solutionTuff Shop
1 official solutionWASM (Weird Assembly)
1 official solution
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
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
Wordle
1 official solution