CVE-2026-84450

Publication date 18 September 2026

Last updated 24 September 2026

Ubuntu priority

Cvss 3 Severity Score

Description

libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, a crafted image item containing a clap property and an ispe width or height greater than INT32_MAX + 1 can reach crop calculations through heif_image_handle_get_image_tiling(). Box_clap::left_rounded() or Box_clap::top_rounded() passes the image dimension minus one to Fraction::Fraction(), whose uint32_t constructor uses an assertion as input validation, causing assert-enabled builds to abort. Release builds can instead compute invalid crop geometry, and the tiling API returns dimensions that the normal decode security limits reject. This issue is fixed in version 1.23.3.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
libheif	26.04 LTS resolute	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected

Notes

kkernick

The backported fix for CVE-2026-62292 included the no-icef branch.

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
libheif	Upstream: 8bfed9a

Severity score breakdown

CVSS version: CVSS v3.0

Base score 4.3 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	Required
Scope	Unchanged
Confidentiality impact	None
Integrity impact	None
Availability impact	Low

Scores

Parameter	Value
Base score	4.3 · Medium
Exploitability score	-
Impact score	-

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L