Break In 2015
12 challenges with 36 published solutions between them. CTFtime lists this event but has no writeups filed against it, so it is absent from the index CTFtime feeds. These were found in public repositories instead. Each link is pinned to the commit it was read from.
The event on CTFtimeForensics5
Recover something from a file, a capture, or a disk image - often from a part of it the format says is unused.
Cheaters
3 official solutionsInvestigator
3 official solutionsSerial Killer
3 official solutionsStrangelmage
3 official solutionsValentines Day
3 official solutions
Reverse engineering4
Work out what a compiled program does without its source, then work backwards from the check to the input that passes it.
Breakingame
3 official solutionsBreakit
3 official solutionsJaggipalace
3 official solutionsRegcomp
3 official solutions
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.
Numbero
3 official solutionsSubstitution
3 official solutions
Misc1
Everything that fits no other box: esolangs, puzzles, scripting exercises, and the jail escapes that have not yet earned their own category.
Heisenberg
3 official solutions