A daily CTF challenge with a fun new puzzle every day
We publish one simple, beginner-friendly or educational CTF challenge every day! Selected problems from external CTFs are released occasionally.
Solve within 24 hours of release to appear on the leaderboard.
Discussion with friends or AI is welcome (account sharing is prohibited).
Sharing solutions is allowed only after 24 hours have passed since release (mirrored past challenges are excluded).
0
/49
No solved challenges yet.
Sign In to view your player stats
Try the first challenge
Is this your first CTF? Let's begin by tackling the first challenge released on Daily AlpacaHack.
Writeups
Topic: C, Flag Checker
flag checker everyone loves
challenge.c and its Ubuntu 24.04 binary build challenge.challenge.c, the flag-related string xor_flag has been edited out and hidden.challenge.c as a reference and find an input (the flag) that makes the challenge binary print Correct.