CVE-2026-47254 libheif Has Heap Buffer Overflow in `Track::get_next_sample_raw_data()` -- OOB Chunk Vector Access
A heap buffer overflow in libheif allows attackers to execute arbitrary code or cause denial of service via crafted HEIF/AVIF files.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-47254?
CVE-2026-47254 is a medium-severity memory corruption vulnerability in strukturag libheif, published on 21 Jul 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
libheif is a HEIF and AVIF file format decoder and encoder. Prior to version 1.22.0, `Track::init_sample_timing_table()` in `libheif/sequences/track.cc` stores an out-of-bounds chunk index (`m_chunks.size()`) into `m_presentation_timeline` when the number of chunks defined in the `stco` box is less than the number of samples in `stsz`. A subsequent call to `heif_track_get_next_raw_sequence_sample()` reads `m_chunks[chunk_idx]` with that OOB index, causing a heap-buffer-overflow. Version 1.22.0 fixes the issue.
Weakness: CWE-125
Which versions are affected by CVE-2026-47254?
It affects 1 product.
Products include Struktur Libheif.
How do I fix CVE-2026-47254?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-47254 being exploited?
There is no known exploitation of CVE-2026-47254 in the wild and no public exploit code.
Other vulnerabilities in strukturag libheif
Sources
Also known as BELL-CVE-2026-47254, DEBIAN-CVE-2026-47254, GHSA-wqjg-4x9g-6cvg, JLSEC-2026-1098, UBUNTU-CVE-2026-47254.