CVE-2026-3949 — Improper Restriction of Operations within the Bounds of a Memory Buffer in Libheif

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.