CVE-2026-40310: ImageMagick: Heap out-of-bounds write in JP2 encoder

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-04-13 · updated 2026-06-17
Weakness: CWE-122

Description

ImageMagick is free and open-source software used for editing and manipulating digital images. Versions below both 7.1.2-19 and 6.9.13-44, contain a heap out-of-bounds write in the JP2 encoder with when a user specifies an invalid sampling index. This issue has been fixed in versions 6.9.13-44 and 7.1.2-19.

Affected products

ImageMagick: before 6.9.13-44; from 7.0.0-0 before 7.1.2-19 — fixed in 6.9.13-44, 7.1.2-19

How to fix

Upgrade to a fixed version: ImageMagick 6.9.13-44, 7.1.2-19. Check the vendor advisory for mitigations.

References

https://github.com/ImageMagick/ImageMagick/commit/3d653bea2df085c728a1c8f775808e1e9249dff9
https://github.com/ImageMagick/ImageMagick/releases/tag/7.1.2-19
https://github.com/ImageMagick/ImageMagick/security/advisories/GHSA-pwg5-6jfc-crvh
https://github.com/dlemstra/Magick.NET/releases/tag/14.12.0

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