Description
libheif is a HEIF and AVIF file format decoder and encoder. Versions 1.21.2 and prior contain a heap-buffer-overflow (write) vulnerability in the grid tile compositing, allowing an attacker to write 64 bytes of fully attacker-controlled data past the end of a chroma plane heap allocation by crafting a HEIF/AVIF file with a 1×4 grid of odd-height tiles. The overflow is triggered during normal image decoding with default build configuration. The written bytes are chroma (Cb/Cr) pixel values from the attacking tile, giving the attacker full control over the overflow content. This issue has been fixed in version 1.22.0.
Affected products
struktur: libheif
References5
- github.com/strukturag/libheif/security/advisories/GHSA-frfr-f3v… ExploitVendor Advisory
- github.com/strukturag/libheif/releases/tag/v1.22.0 Release Notes
- access.redhat.com/security/cve/CVE-2026-32740
- bugzilla.redhat.com/show_bug.cgi?id=2479969
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-32740…
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 53 · as of 14 November 2026
- CWE
- CWE-787
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