HEIF and AVIF File Format Decoder Vulnerability in libheif by Struktur AG
CVE-2026-84447

7.5HIGH

Key Information:

Vendor

Strukturag

Status
Libheif
Vendor
CVE Published:
18 September 2026

What is CVE-2026-84447?

libheif, a library for encoding and decoding HEIF and AVIF file formats, has a vulnerability that allows specially crafted grid, iovl, and iden reference graphs to continuously decode the same base image. This situation arises due to the erroneous handling of processed_ids across branches, as ImageItem::decode_image() lacks a shared operation budget, leading to potential performance degradation. This issue has been addressed in version 1.23.2, where appropriate fixes have been implemented.

Affected Version(s)

libheif < 1.23.2

References

https://github.com/strukturag/libheif/security/advisories...
x_refsource_CONFIRM
https://github.com/strukturag/libheif/commit/30b52a4e829e...
x_refsource_MISC
https://github.com/strukturag/libheif/releases/tag/v1.23.2
x_refsource_MISC

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.