This CTFd instance has a bunch of security CTF challenges written by kuilin. All of them are hard, some exceptionally hard.
All of these are solvable with only info from CTFd, but here's the repo these are deployed from: https://github.com/likuilin/ctf-challenges
Of course, the write-ups contain solutions. The flags were updated for this deployment, though (at least, the ones where they're changeable).
| Name | Public Release | Short Non-Spoilers Description | Solved/Teams | Write-ups |
|---|---|---|---|---|
| wasmcloud | 2021-07-30 in UIUCTF 2021 | Break a web service that runs your webassembly on the server |
0*/1069 | 1 |
| pow_erful | 2021-07-30 in UIUCTF 2021 | Cheat a sha256 proof of work | 16/1069 | 1 |
| Who is GDB? | 2020-07-17 in UIUCTF 2020 | Break a GDB server (...server?) | 2/882 | None‡ |
| cricket32 | 2020-07-17 in UIUCTF 2020 | Strangely short x86 reversing, now with 100% less angr-ability |
11/882 | 1, 2, 3 |
| ouroboros | 2020-02-04 in sigpwny CTF† | Strangely short x86 reversing | N/A | None |
| trapezoid | 2019-08-15 in sigpwny CTF† | LC-3 assembly reversing | N/A | None |
*wasmcloud had zero solves by the end of the event, and was only first solved 18 hours after the event ended by the write-up author.
‡Who is GDB? was the only challenge in UIUCTF 2020 that did not get any write-ups.
†sigpwny CTF is a private internal CTF for sigpwny that was long-running and generally had no write-ups.