Vulnerability · Published Jun 19, 2026 · Assigned by GitHub_M

CVE-2026-49271libheif: Wrapped icef compressed-unit range check causes out-of-bounds read in uncompressed HEIF decoder

Medium 6.5

In plain English

A medium-severity out-of-bounds read in libheif from strukturag. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)6.5Medium

Exploit odds (30 days)0.4%top 70.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

libheif is a HEIF and AVIF file format decoder and encoder. Prior to version 1.22.1, the uncompressed HEIF decoder validates explicit icef compressed-unit offsets using unit_offset + unit_size. Because the addition can wrap, a crafted HEIF file can pass the range check and then construct a vector from iterators outside the compressed item buffer, producing an out-of-bounds heap read and crash. Version 1.22.1 patches the issue.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	libheif	no fix listed	DEBIAN-CVE-2026-49271
Debian:13	libheif	1.19.8-1+deb13u1	DEBIAN-CVE-2026-49271
Debian:14	libheif	1.23.1-1	DEBIAN-CVE-2026-49271
Ubuntu:26.04:LTS	libheif	1.21.2-3ubuntu0.2	UBUNTU-CVE-2026-49271

Affected products (as reported)

Vendor	Product	Versions
strukturag	libheif	< 1.22.1

Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

References

https://github.com/strukturag/libheif/security/advisories/GHSA-r7qj-cg5r-r6vf x_refsource_CONFIRM