CVE-2026-47251

MEDIUM
MEDIUM Priority: 0.01 BB Relevance: 39/100
Published: 2026-07-21 Modified: 2026-10-24 First seen: 2026-10-29 Status: active

Attack Surface

Low Complexity No Auth

CVSS Vector Breakdown

AV: Local
AC: Low
PR: None
UI: Active
S: X
AT: None
VC: Low
VI: None
VA: High

Description

libheif is a HEIF and AVIF file format decoder and encoder. The fix for CVE-2026-3949 (commit `b97c8b5`, PR #1712) introduced an integer overflow in the very security check it added. The check itself can be bypassed, allowing a crafted HEIF file with a VVC track to trigger the same out-of-bounds heap read that CVE-2026-3949 was meant to prevent. This is a separate, currently-unpatched vulnerability. Issue #1712 was closed as fixed without testing the edge case where `size` is near `UINT32_MAX`. Version 1.22.0 patches the issue.

Weakness Classification (2)

Affected Software (1)

VendorProductVersion
struktur libheif < 1.22.0

Bug Bounty Relevance

39 / 100
✓ No authentication
✓ Low complexity

CVSS Score

6.8 / 10.0 v4.0
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS — Exploitation Probability

0.16%
Raw Score 0.001590
Percentile 5.0%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00159
2026-10-28
0.00159

Intelligence Sources

nvd ref →