CVE-2026-47709 libheif has a NULL pointer dereference in heif_image_handle_get_image_tiling for malformed unci image missing ispe

Medium 6.9 Published 21 Jul 2026 Updated 22 Jul 2026

A malformed HEIF image causes a null pointer dereference in libheif, leading to application crashes during image tiling retrieval.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2026-47709?

CVE-2026-47709 is a medium-severity vulnerability in strukturag libheif, published on 21 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

libheif is a HEIF and AVIF file format decoder and encoder. Versions prior to 1.22.0 crashes in the public C API `heif_image_handle_get_image_tiling()` when a malformed uncompressed HEIF image item has an associated `uncC` property but no associated `ispe` property. In debug builds this trips the `ispe && uncC` assertion in `ImageItem_uncompressed::get_heif_image_tiling()`. In a release/NDEBUG ASan build, the same file causes a null pointer read at address `0xa8`. Version 1.22.0 fixes the issue.

Weakness: CWE-476

Which versions are affected by CVE-2026-47709?

It affects 1 product.

Products include Struktur Libheif.

How do I fix CVE-2026-47709?

Upgrade to a fixed version.

Is CVE-2026-47709 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-47709 exists.

Sources

Also known as BELL-CVE-2026-47709, DEBIAN-CVE-2026-47709, ECHO-4429-8097-b109, GHSA-4h72-vqgp-9376, JLSEC-2026-1099, UBUNTU-CVE-2026-47709.