GPN CTF 2025
9 challenges with 15 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 exploitation5
Turn a memory-safety bug in a native binary into control of execution. Usually a stack overflow, a format string, or a heap primitive.
Also written up in: s41nt0l3xus/CTF-writeups, s41nt0l3xus/CTF-writeups
- 0day
- browser
- pwn
- ladybird
Same technique in picoCTF: lockdown-horses, Guessing Game 1, Bizz Fuzz
Also written up in: binneko/ctf-writeups, binneko/ctf-writeups
Note Editor
2 official solutionsAlso written up in: binneko/ctf-writeups, binneko/ctf-writeups
Honeypot
1 official solutionAlso written up in: pwn-la-chapelle.eu
Paranoid
1 official solutionAlso written up in: pwn-la-chapelle.eu
Uncategorised2
The upstream scoreboard did not say, so neither do we.
Hinting
1 official solutionAlso written up in: atuc17/CTF
Response
1 official solutionAlso written up in: s41nt0l3xus/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.
- crypto
- oracle-padding
Same technique in picoCTF: It's Not My Fault 2, StegoRSA, AES-ABC
Web1
Reach data or functionality the application meant to keep from you - through its inputs, its tokens, or its trust in the client.
Free Flagging
2 official solutionsAlso written up in: binneko/ctf-writeups, binneko/ctf-writeups