# CVE-2026-109964: ImageMagick heap buffer underwrite in PICT decoder

Source: https://junglewise.ai/threats/cve-2026-109964-imagemagick-before-7-1-2-33-and-6-9-13-58-contains-a-heap-buffer  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-13. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-109964 · Severity: medium · CVSS 5.6 · Published 2026-10-13

ImageMagick is an image processing library used to convert and manipulate image files. A heap buffer underwrite vulnerability in its PICT format decoder allows attackers who provide a crafted PICT file to write controlled bytes below a heap buffer, potentially causing the application to crash or execute arbitrary code.

Technologies: [ImageMagick](https://junglewise.ai/threats/technologies/imagemagick). Vendors: [ImageMagick](https://junglewise.ai/threats/vendors/imagemagick).

## Quick answers

**Is CVE-2026-109964 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-109964 being exploited in the wild.

**How severe is CVE-2026-109964?** Medium severity, with a CVSS score of 5.6, published 13 October 2026.

**Which products and versions are affected?** ImageMagick before 7.1.2-33 and 6.9.13-58 (32-bit builds).

**Is there a fix for CVE-2026-109964?** Yes: fixed in ImageMagick 7.1.2-33, 6.9.13-58. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-109964 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-109964?** Check whether you run ImageMagick 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.

## How to fix

- Fixed in ImageMagick 7.1.2-33, 6.9.13-58

## Technical details

The vulnerability is a heap buffer underwrite in DecodeImage() in coders/pict.c, caused by pointer arithmetic overflow on 32-bit builds. Attackers supply a crafted PICT file with maximized row, column, and bytes-per-line values to bypass bounds checks and write up to 128 controlled bytes below the heap buffer. This requires the attacker to provide a malicious PICT file to an application using ImageMagick, with no authentication or user privileges needed beyond file access.

## Affected products

- ImageMagick ImageMagick before 7.1.2-33 and 6.9.13-58 (32-bit builds)

## Timeline

- 2026-10-13: disclosed

## References

- [https://github.com/ImageMagick/ImageMagick](https://github.com/ImageMagick/ImageMagick)
- [https://github.com/ImageMagick/ImageMagick/blob/7.1.2-32/coders/pict.c](https://github.com/ImageMagick/ImageMagick/blob/7.1.2-32/coders/pict.c)

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