Vulnerability details

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.

• https://github.com/strukturag/libheif/security/advisories/GHSA-frfr-f3vg-2g6j x_refsource_CONFIRM
• https://github.com/strukturag/libheif/releases/tag/v1.22.0 x_refsource_MISC
• https://access.redhat.com/security/cve/CVE-2026-32740 vdb-entryx_refsource_REDHAT
• https://bugzilla.redhat.com/show_bug.cgi?id=2479969 issue-trackingx_refsource_REDHAT
• https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-32740.json x_sadp-csaf-vex