CVE-2026-84448

Updated on 18 Sep 2026

Severity

4.0 Medium severity

Details

CVSS score
4.0
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L

Overview

About vulnerability

libheif is a HEIF and AVIF file format decoder and encoder. Prior to 1.23.2, the public heif_region_item_add_region_inline_mask_data() function in libheif/api/libheif/heif_regions.cc accepts mask_data_len without verifying that it equals the byte count required by width and height. A later heif_region_get_mask_image() call derives the read length from the region geometry, so an undersized stored buffer causes heif_region_get_inline_mask_image() to read beyond the heap allocation and copy adjacent bytes into the returned monochrome mask image. This can disclose heap data or crash an application that constructs region metadata through the writer API, while the file-parsing path is not affected because it validates the canonical mask size. This issue is fixed in version 1.23.2.

Details

Affected product:
Debian 11 ELS
Affected packages:
libheif @ 1.11.0

Fixes