ImageMagick stack buffer overflow in MNG encoder

Severity: medium · CVSS 6.9 · Published 2026-04-14

ImageMagick, a widely used suite for editing and converting digital images, contains a vulnerability in how it handles certain multi-frame image files. An attacker could provide a specially crafted image with an oversized color palette to cause a system crash or potentially execute unauthorized code. This could lead to service disruptions or unauthorized access to data on systems that process user-uploaded images.

Technologies: Magick.NET-Q16-AnyCPU (NuGet), Magick.NET-Q16-arm64 (NuGet), Magick.NET-Q16-HDRI-AnyCPU (NuGet), Magick.NET-Q16-HDRI-arm64 (NuGet), Magick.NET-Q16-HDRI-OpenMP-arm64 (NuGet), Magick.NET-Q16-HDRI-OpenMP-x64 (NuGet), Magick.NET-Q16-HDRI-x64 (NuGet), Magick.NET-Q16-HDRI-x86 (NuGet), Magick.NET-Q16-OpenMP-arm64 (NuGet), Magick.NET-Q16-OpenMP-x64 (NuGet), Magick.NET-Q16-x64 (NuGet), Magick.NET-Q16-x86 (NuGet), Magick.NET-Q8-AnyCPU (NuGet), Magick.NET-Q8-arm64 (NuGet), Magick.NET-Q8-OpenMP-arm64 (NuGet), Magick.NET-Q8-OpenMP-x64 (NuGet), Magick.NET-Q8-x64 (NuGet), Magick.NET-Q8-x86 (NuGet). Vendors: NuGet.

Quick answers

Is This vulnerability exploited in the wild?
No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?
Medium severity, with a CVSS score of 6.9, published 14 April 2026.
Which products and versions are affected?
Magick.NET-Q16-AnyCPU (NuGet) < 14.12.0; Magick.NET-Q16-arm64 (NuGet) < 14.12.0; Magick.NET-Q16-HDRI-AnyCPU (NuGet) < 14.12.0; Magick.NET-Q16-HDRI-arm64 (NuGet) < 14.12.0; and 14 more.
Is there a fix for This vulnerability?
A patch was published on 2026-04-14. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is This vulnerability attacked?
It is attacked with local access, in a software library.
Am I affected?
Check whether you run Magick.NET-Q16-AnyCPU (NuGet), Magick.NET-Q16-arm64 (NuGet), Magick.NET-Q16-HDRI-AnyCPU (NuGet) or one of the others listed 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

A stack-based buffer overflow (CWE-121) exists in the ImageMagick MNG encoder. The vulnerability is caused by an incomplete fix for a previous issue, where the encoder fails to properly validate the size of palettes in multi-frame images. A local attacker can exploit this by providing a malicious image file, potentially leading to arbitrary code execution or a denial-of-service (DoS) condition. The vulnerability is addressed in Magick.NET version 14.12.0.

Affected products

  • ImageMagick Magick.NET-Q16-AnyCPU < 14.12.0
  • ImageMagick Magick.NET-Q16-HDRI-AnyCPU < 14.12.0
  • ImageMagick Magick.NET-Q16-HDRI-OpenMP-arm64 < 14.12.0
  • ImageMagick Magick.NET-Q16-HDRI-OpenMP-x64 < 14.12.0
  • ImageMagick Magick.NET-Q16-HDRI-arm64 < 14.12.0
  • ImageMagick Magick.NET-Q16-HDRI-x64 < 14.12.0
  • ImageMagick Magick.NET-Q16-HDRI-x86 < 14.12.0
  • ImageMagick Magick.NET-Q16-OpenMP-arm64 < 14.12.0
  • ImageMagick Magick.NET-Q16-OpenMP-x64 < 14.12.0
  • ImageMagick Magick.NET-Q16-arm64 < 14.12.0
  • ImageMagick Magick.NET-Q16-x64 < 14.12.0
  • ImageMagick Magick.NET-Q16-x86 < 14.12.0
  • ImageMagick Magick.NET-Q8-AnyCPU < 14.12.0
  • ImageMagick Magick.NET-Q8-OpenMP-arm64 < 14.12.0
  • ImageMagick Magick.NET-Q8-OpenMP-x64 < 14.12.0
  • ImageMagick Magick.NET-Q8-arm64 < 14.12.0
  • ImageMagick Magick.NET-Q8-x64 < 14.12.0
  • ImageMagick Magick.NET-Q8-x86 < 14.12.0

Timeline

  • 2026-04-13: disclosed
  • 2026-04-14: advisory
  • 2026-04-14: patched

References

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