CVE-2026-3949 strukturag libheif HEIF File decoder_vvdec.cc vvdec_push_data2 out-of-bounds
A local attacker can trigger an out-of-bounds read in libheif's HEIF decoder, potentially causing crashes or leaking memory.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-3949?
CVE-2026-3949 is a medium-severity memory corruption vulnerability in strukturag libheif, published on 11 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A vulnerability was determined in strukturag libheif up to 1.21.2. This affects the function vvdec_push_data2 of the file libheif/plugins/decoder_vvdec.cc of the component HEIF File Parser. Executing a manipulation of the argument size can lead to out-of-bounds read. The attack needs to be launched locally. The exploit has been publicly disclosed and may be utilized. This patch is called b97c8b5f198b27f375127cd597a35f2113544d03. It is advisable to implement a patch to correct this issue.
Which versions are affected by CVE-2026-3949?
Linux distribution packages (1)
libheif openSUSE:Tumbleweed | All versions | 1.21.2-2.1 |
How do I fix CVE-2026-3949?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-3949 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-3949 exists.
Sources
Also known as DEBIAN-CVE-2026-3949, ECHO-335c-65c6-bca4, GHSA-2rvx-jpm5-g848, SUSE-SU-2026:1660-1, openSUSE-SU-2026:10460-1.