Lexington Informatics Tournament CTF 2021
23 challenges with 29 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 CTFtimeBinary exploitation10
Turn a memory-safety bug in a native binary into control of execution. Usually a stack overflow, a format string, or a heap primitive.
- ret2libc
- pwn
Same technique in picoCTF: Guessing Game 1, x-sixty-what, format string 3
- bof
- pwn
Same technique in picoCTF: Guessing Game 1, x-sixty-what, PIE TIME 2
- fmtstr
- pwn
Same technique in picoCTF: Guessing Game 1, x-sixty-what, format string 3
- bof
- pwn
Same technique in picoCTF: Guessing Game 1, x-sixty-what, PIE TIME 2
- pwn
- heap
Same technique in picoCTF: tea-cash, sice_cream, zero_to_hero
- pwn
- fmtstr
Same technique in picoCTF: Guessing Game 1, x-sixty-what, format string 3
- pwn
- heap
Same technique in picoCTF: tea-cash, sice_cream, zero_to_hero
- fmtstr
- pwn
Same technique in picoCTF: Guessing Game 1, x-sixty-what, format string 3
- fmtstr
- pwn
Same technique in picoCTF: Guessing Game 1, x-sixty-what, format string 3
- pwn
- fmtstr
Same technique in picoCTF: Guessing Game 1, x-sixty-what, format string 3
Reverse engineering5
Work out what a compiled program does without its source, then work backwards from the check to the input that passes it.
- python
- rev
- eval
Same technique in picoCTF: keygenme-py, Shop, patchme.py
- rev
Same technique in picoCTF: WinAntiDbg0x100, WinAntiDbg0x200, WinAntiDbg0x300
- rev
Same technique in picoCTF: WinAntiDbg0x100, WinAntiDbg0x200, WinAntiDbg0x300
- rev
Same technique in picoCTF: WinAntiDbg0x100, WinAntiDbg0x200, WinAntiDbg0x300
- rev
Same technique in picoCTF: WinAntiDbg0x100, WinAntiDbg0x200, WinAntiDbg0x300
Web4
Reach data or functionality the application meant to keep from you - through its inputs, its tokens, or its trust in the client.
- websockets
- web
Same technique in picoCTF: Client-side-again, dont-use-client-side, Irish-Name-Repo 3
- blacklistbypass
- web
- sqli
Same technique in picoCTF: Irish-Name-Repo 3, More SQLi, Secret Box
- xxe
- web
Same technique in picoCTF: Client-side-again, dont-use-client-side, Irish-Name-Repo 3
- web
Same technique in picoCTF: Client-side-again, dont-use-client-side, Irish-Name-Repo 3
Cryptography2
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.
- aes
- pcbc
- crypto
- oracle-padding
Same technique in picoCTF: Timestamped Secrets, AES-ABC, Compress and Attack
- primitive_roots
- crt
- root_of_unity
- crypto
- modular-root
Same technique in picoCTF: StegoRSA, Timestamped Secrets, AES-ABC
OSINT2
Answer a question about the real world from public sources. The work is pivoting between identifiers, not exploiting anything.
- osint
- misc
Same technique in picoCTF: Permissions, Specialer, Codebook
- misc
- osint
Same technique in picoCTF: Permissions, Specialer, Codebook