Is CVE-2026-52584 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-52584 being exploited in the wild.

How severe is CVE-2026-52584?

Informational severity, with a CVSS score of 0, published 17 July 2026.

Which products and versions are affected?

libjxl libjxl v0.11.2 and earlier.

Is there a fix for CVE-2026-52584?

A patch was published on 2026-05-27: Fix submitted and approved via pull request Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-52584 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2026-52584?

Check whether anything you run is named in the advisory. 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-2026-52584: libjxl heap buffer overflow in DecodeImageAPNG

CVE-2026-52584 · Severity: info · CVSS 0 · Published 2026-07-17

libjxl is an open-source library used for encoding and decoding JPEG XL images. A security flaw was discovered where the library incorrectly handles certain animated PNG (APNG) files, which could allow a local attacker to access sensitive information from the computer's memory. This could lead to the exposure of private data or help an attacker bypass other security protections on the system.

Quick answers

Is CVE-2026-52584 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-52584 being exploited in the wild.
How severe is CVE-2026-52584?: Informational severity, with a CVSS score of 0, published 17 July 2026.
Which products and versions are affected?: libjxl libjxl v0.11.2 and earlier.
Is there a fix for CVE-2026-52584?: A patch was published on 2026-05-27: Fix submitted and approved via pull request Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-52584 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-52584?: Check whether anything you run is named in the advisory. 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

A heap-based buffer overflow vulnerability exists in libjxl's APNG decoding logic within the `DecodeImageAPNG` function in `lib/extras/dec/apng.cc`. The flaw is triggered when the library fails to properly validate `frameRaw.rows` bounds before memory access during the decoding of an animated PNG. A local attacker can exploit this by providing a specially crafted APNG file to an application using the library (such as the `cjxl` tool). This results in an out-of-bounds read, potentially leaking sensitive information from the heap. A fix was submitted in pull request #4804 involving improved bounds validation.

Affected products

libjxl libjxl v0.11.2 and earlier

Timeline

2026-05-26: disclosed: Issue reported on GitHub
2026-05-27: patched: Fix submitted and approved via pull request
2026-07-17: advisory: CVE published to NVD

References

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