---
id: CVE-2026-84444
title: libheif is a HEIF and AVIF file format decoder and encoder
summary: >-
  libheif is a HEIF and AVIF file format decoder and encoder. Prior to 1.23.2,
  when WITH_UNCOMPRESSED_CODEC is enabled, heif_context_add_image_tile() accepts
  an independently constructed tile whose component-plane dimensions do not
  match t…
severity: high
cvss: 7.4
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H'
cwe:
  - CWE-787
vendor: strukturag
product: libheif
affected:
  - libheif < 1.23.2
published: '2026-09-18'
updated: '2026-09-22'
sourceUpdated: '2026-09-22T15:17:19.093'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-84444'
references:
  - url: >-
      https://github.com/strukturag/libheif/commit/e65071f59a1ac08aa1eb0d07a831deaf6bb4d03b
    label: security-advisories@github.com
  - url: 'https://github.com/strukturag/libheif/releases/tag/v1.23.2'
    label: security-advisories@github.com
  - url: >-
      https://github.com/strukturag/libheif/security/advisories/GHSA-j264-xvrp-5v7q
    label: security-advisories@github.com
  - url: >-
      https://github.com/strukturag/libheif/security/advisories/GHSA-j264-xvrp-5v7q
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-22T14:50:07.797725Z'
epss: 0.0053
epssPercentile: 0.42282
ingestedAt: '2026-09-18T16:45:41.394Z'
---

## Overview

libheif is a HEIF and AVIF file format decoder and encoder. Prior to 1.23.2, when WITH_UNCOMPRESSED_CODEC is enabled, heif_context_add_image_tile() accepts an independently constructed tile whose component-plane dimensions do not match the tile geometry established by the prototype image. ImageItem_uncompressed::add_image_tile() passes that tile directly to unc_encoder::encode_tile(), which lacked the check_component_sizes() gate and sizes its output from the configured tile geometry while copying the tile's actual component-plane dimensions. An oversized component plane can therefore make unc_encoder_component_interleave::encode_tile() copy attacker-controlled data beyond the heap output buffer. This issue is fixed in version 1.23.2.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.