CVE-2026-84451

MEDIUM

6.5

CVSS v3

Description

libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, the no-icef full-item branch of unc_decoder::get_compressed_image_data_uncompressed() in libheif/codecs/uncompressed/unc_decoder.cc retains an addition-based range check that can wrap when a crafted uncompressed tile grid produces a large range_start_offset and range_size. The overflow makes the bounds comparison pass and allows heif_image_handle_decode_image_tile() to call memcpy() with an invalid source pointer and a very large length when decoding a valid high-index advertised tile. This incomplete remediation of CVE-2026-62292 can reliably crash tile-processing applications, while whole-image decoding is not claimed to reach the demonstrated path. This issue is fixed in version 1.23.3.

CWE-125Out-of-bounds Read

How to fix

Remediation Available

libheifDebian

Fixed in:1.23.3-1CVE-2026-84451

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionRequired

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityNone

AvailabilityHigh

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

Exploit Intelligence

EPSS data unavailable for this CVE.

References

Other references3

Related Vulnerabilities

Other CWE-125 (Out-of-bounds Read) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2014-0160	High	7.5	100%	KEV	Fix
CVE-2025-5777	High	7.5	100%	KEV + Ransom	Fix
CVE-2021-4034	High	7.8	95%	KEV + Ransom	Fix
CVE-2020-8794	Critical	9.8	89%	-	Fix
CVE-2023-21769	High	7.5	89%	-	Fix
CVE-2023-49285	High	8.6	88%	-	Fix

Common questions

How do I fix CVE-2026-84451?

Upgrade libheif on debian unstable to 1.23.3-1 or later.

How severe is CVE-2026-84451?

CVE-2026-84451 has a CVSS v3 base score of 6.5, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2026-84451 affect?

Published advisories record a fix for libheif (Debian). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2026-84451

Markdown

[![CVE-2026-84451](https://tridentstack.com/cve/badge/CVE-2026-84451.svg)](https://tridentstack.com/cve/CVE-2026-84451)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-84451"><img src="https://tridentstack.com/cve/badge/CVE-2026-84451.svg" alt="CVE-2026-84451"></a>

Check your Linux endpoints for this class of vulnerability

TridentStack Control continuously scans Linux endpoints for known vulnerabilities and deploys the fixes from the same console. 200 endpoints free forever, no credit card.

Patch your fleet free Start freeThis CVE lookup is free and always will be.

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-09-18.