#variant-analysis

3 writeups.

The right bugs, the wrong repo: fuzzing libtsm and catching an upstream redirect 17 Aug 2026

Three memory-safety bugs in libtsm's terminal escape-sequence parser — but the part worth remembering isn't the bugs, it's how a clean-gate target got chosen from a thin pool, and the moment the fork I fuzzed turned out to be the wrong place to send the report.

fuzzing libtsm coordinated-disclosure variant-analysis target-selection memory-safety
The sibling a same-day public fix missed: four memory-safety bugs in zchunk 3 Aug 2026

I reported four memory-safety bugs in zchunk privately; the same afternoon an independent contributor opened a public PR fixing one of them — but not its sibling. The part worth remembering is how a narrow fix leaves a matching hole one field over, and why reporting the whole cluster matters.

coordinated-disclosure zchunk fuzzing variant-analysis memory-safety
The bug that was already fixed: a missing backport in libebml 24 Jul 2026

A malformed-input path in libebml's EBML reader was already guarded on the v1.x branch but never forward-ported to master — a look at the missing-backport bug class and being wrong about a PoC while still being useful.

fuzzing libebml matroska variant-analysis coordinated-disclosure