Heap Buffer Overflow in libheif HEIF/AVIF Decoder
CVE-2026-32740

8.8HIGH

Key Information:

Vendor

Strukturag

Status
Libheif
Vendor
CVE Published:
19 May 2026

What is CVE-2026-32740?

libheif, a popular decoder and encoder for HEIF and AVIF file formats, is susceptible to a heap buffer overflow vulnerability during image decoding. This flaw occurs in versions 1.21.2 and earlier, where an attacker can craft a malicious HEIF/AVIF file containing a 1Ă—4 grid of oddly-dimensioned tiles. The vulnerability allows the attacker to write up to 64 bytes of arbitrary data beyond the bounds of a heap allocation for chroma plane values (Cb/Cr). Exploitation of this vulnerability can lead to unexpected behavior, data leakage, or control over the affected software. The issue has been addressed and resolved in version 1.22.0.

Affected Version(s)

libheif < 1.22.0

References

https://github.com/strukturag/libheif/security/advisories...
x_refsource_CONFIRM
https://github.com/strukturag/libheif/releases/tag/v1.22.0
x_refsource_MISC

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.