Out-of-Bounds Read in HEIF File Parser Affects strukturag Product
CVE-2026-3949

4.8MEDIUM

Key Information:

Vendor

Strukturag

Status
Libheif
Vendor
CVE Published:
11 March 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-3949?

A vulnerability exists within strukturag's HEIF File Parser, specifically in the vvdec_push_data2 function of decoder_vvdec.cc. By manipulating the argument size, it is possible to trigger an out-of-bounds read, which may lead to information disclosure or other security risks. This vulnerability must be exploited locally, necessitating access to the affected system. The issue has been publicly disclosed, and a corresponding patch is available for implementation to mitigate the risk.

Affected Version(s)

libheif 1.21.0

libheif 1.21.1

libheif 1.21.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-3949 - Proof of Concept

References

https://vuldb.com/?id.350381
vdb-entrytechnical-description
https://vuldb.com/?ctiid.350381
signaturepermissions-required
https://vuldb.com/?submit.765979
third-party-advisory

CVSS V4

Score:
4.8
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
Low
Attack Vector:
Local
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

biniam (VulDB User)
.