CVE-2026-48029 libheif: heap OOB read in ImageItem_Grid::decode_grid_tile via irot-induced tile-coordinate underflow

High 7.1 Published 22 Jul 2026 Updated 22 Jul 2026

A heap out-of-bounds read in libheif allows attackers to cause denial of service or disclose memory contents via crafted image files.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: A user has to click or open something
Fix: Available

What is CVE-2026-48029?

CVE-2026-48029 is a high-severity memory corruption vulnerability in strukturag libheif, published on 22 Jul 2026. An attacker can exploit it over the internet without logging in, 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. Versions 1.19.0 through 1.21.2 have a heap OOB read in ImageItem_Grid::decode_grid_tile via irot-induced tile-coordinate underflow. Version 1.22.0 fixes the issue.

Weakness: CWE-191, CWE-125

Which versions are affected by CVE-2026-48029?

It affects 1 product.

Products include Struktur Libheif.

How do I fix CVE-2026-48029?

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-2026-48029 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48029 exists.

Sources

Also known as BELL-CVE-2026-48029, DEBIAN-CVE-2026-48029, ECHO-f301-3bae-8fc2, GHSA-6x5f-qchq-cxqv, JLSEC-2026-1193, ROOT-OS-DEBIAN-12-CVE-2026-48029 and 1 more.