CVE-2026-48029: Two grid-decode bugs in libheif
Vulnerability research - CVE-2026-48029 · Public / PatchedA single afternoon of fuzzing against libheif 1.21.2 produced two memory-safety bugs in the same function. F1 is a NULL pointer dereference on a malformed grid dimg reference - deterministic DoS-on-decode from any public decode API. F2 is a uint32 underflow in the inverse-rotation tile arithmetic that feeds a debug-only assert; in NDEBUG release builds (the configuration typical distribution packages use) the assert is compiled out and the access becomes a heap out-of-bounds read with an attacker-influenced offset. Reported privately on 2026-05-02; fixed in libheif 1.22.0 on 2026-05-19. Tracked as GHSA-6x5f-qchq-cxqv and assigned CVE-2026-48029.