$ cat writeup.md…
$ cat writeup.md…
broncoctf2026
Task: a corrupted challenge.png that no viewer can open, with a wiped PNG signature, zeroed IHDR height, and invalid chunk CRCs. Solution: restore the 8-byte magic signature, derive the missing height (200) from the inflated IDAT scanline geometry, recompute every chunk CRC32, then OCR the repaired image for the flag.
Permission denied (requires tier.pro)
Sign in with GitHub, Discord, or Google to continue. No email required.
$sign in$ grep --similar