Is CVE-2026-84444 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-84444 being exploited in the wild.

How severe is CVE-2026-84444?

High severity, with a CVSS score of 7.4, published 18 September 2026.

Which products and versions are affected?

Strukturag Libheif before 1.23.2.

Is there a fix for CVE-2026-84444?

A patch was published on 2026-08-24. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-84444 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-84444?

Check whether you run Strukturag Libheif at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-84444: libheif heap buffer overflow in uncompressed encoder

CVE-2026-84444 · Severity: high · CVSS 7.4 · Published 2026-09-18

libheif is a decoder and encoder for HEIF and AVIF image formats used by many applications to handle modern image files. When the uncompressed codec feature is enabled, an attacker can craft a malicious image file with incorrectly sized tile data that causes a heap buffer overflow, potentially leading to data corruption, information disclosure, or remote code execution.

Technologies: Strukturag Libheif. Vendors: Strukturag.

Quick answers

Is CVE-2026-84444 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-84444 being exploited in the wild.
How severe is CVE-2026-84444?: High severity, with a CVSS score of 7.4, published 18 September 2026.
Which products and versions are affected?: Strukturag Libheif before 1.23.2.
Is there a fix for CVE-2026-84444?: A patch was published on 2026-08-24. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-84444 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-84444?: Check whether you run Strukturag Libheif at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability exists in the unci encoder's tile handling path when WITH_UNCOMPRESSED_CODEC is enabled. The heif_context_add_image_tile() function accepts independently constructed tiles whose component-plane dimensions do not match the tile geometry, and passes them to unc_encoder::encode_tile() which lacks validation and sizes its output buffer based on the prototype image's configuration while copying from the tile's actual dimensions, causing a heap buffer overflow. The fix adds comprehensive validation gates to encode_tile() that verify colorspace, chroma format, component properties, and plane sizes against the prototype before encoding.

Affected products

strukturag libheif before 1.23.2

Timeline

2026-09-18: disclosed
2026-08-24: patched

References

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