SB20260819128 - Ubuntu update for libheif



SB20260819128 - Ubuntu update for libheif

Published: August 19, 2026

Security Bulletin ID SB20260819128
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 50% Low 50%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 vulnerabilities.


1) Integer underflow (CVE-ID: CVE-2026-62289)

CWE-ID: CWE-191 - Integer underflow

CVSSv4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to integer underflow in the Fraction constructor when processing a crafted HEIF/AVIF file through the tiling API with process_image_transformations=1. A remote attacker can supply a specially crafted file to cause a denial of service.

User interaction is required to open the crafted file, or the issue can be triggered server-side when uploaded content is processed automatically.


2) Out-of-bounds read (CVE-ID: CVE-2026-62292)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to out-of-bounds read in unc_decoder::get_compressed_image_data_uncompressed() when decoding an advertised image tile from a crafted HEIF uncompressed image through heif_image_handle_decode_image_tile(). A remote attacker can supply a specially crafted HEIF file and trigger tile decoding to cause a denial of service.

The issue is not triggered by merely opening the file; the vulnerable path is reached when an application enumerates tiling metadata and decodes an advertised tile.


Remediation

Install update from vendor's website.