# CVE-2026-40169: ImageMagick heap overflow in YAML and JSON encoders

Source: https://junglewise.ai/threats/cve-2026-40169-imagemagick-heap-overflow-in-yaml-and-json-encoders  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-13. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2026-40169 · Severity: medium · CVSS 6.2 · Published 2026-04-13

ImageMagick is a widely used software suite for displaying, converting, and editing image files. A vulnerability in how it handles certain data formats could allow a specially crafted image to cause the application to crash. This could lead to a denial-of-service, impacting the availability of automated image processing workflows.

Technologies: [Dlemstra Magick.NET](https://junglewise.ai/threats/technologies/magick-net), [ImageMagick](https://junglewise.ai/threats/technologies/imagemagick), [Magick.NET-Q16-AnyCPU (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q16-anycpu), [Magick.NET-Q16-arm64 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q16-arm64), [Magick.NET-Q16-HDRI-AnyCPU (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q16-hdri-anycpu), [Magick.NET-Q16-HDRI-arm64 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q16-hdri-arm64), [Magick.NET-Q16-HDRI-OpenMP-arm64 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q16-hdri-openmp-arm64), [Magick.NET-Q16-HDRI-x64 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q16-hdri-x64), [Magick.NET-Q16-HDRI-x86 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q16-hdri-x86), [Magick.NET-Q16-OpenMP-arm64 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q16-openmp-arm64), [Magick.NET-Q16-OpenMP-x64 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q16-openmp-x64), [Magick.NET-Q16-x64 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q16-x64), [Magick.NET-Q16-x86 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q16-x86), [Magick.NET-Q8-AnyCPU (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q8-anycpu), [Magick.NET-Q8-arm64 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q8-arm64), [Magick.NET-Q8-OpenMP-arm64 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q8-openmp-arm64), [Magick.NET-Q8-OpenMP-x64 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q8-openmp-x64), [Magick.NET-Q8-x64 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q8-x64), [Magick.NET-Q8-x86 (NuGet)](https://junglewise.ai/threats/technologies/magick-net-q8-x86). Vendors: [Dlemstra](https://junglewise.ai/threats/vendors/dlemstra), [ImageMagick](https://junglewise.ai/threats/vendors/imagemagick), [NuGet](https://junglewise.ai/threats/vendors/nuget).

## Quick answers

**Is CVE-2026-40169 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-40169 being exploited in the wild.

**How severe is CVE-2026-40169?** Medium severity, with a CVSS score of 6.2, published 13 April 2026.

**Which products and versions are affected?** Dlemstra Magick.NET < 14.12.0; Magick.NET-Q16-AnyCPU (NuGet) < 14.12.0, ECOSYSTEM:introduced=0,fixed=14.12.0; Magick.NET-Q16-arm64 (NuGet) < 14.12.0, ECOSYSTEM:introduced=0,fixed=14.12.0; Magick.NET-Q16-HDRI-AnyCPU (NuGet) < 14.12.0, ECOSYSTEM:introduced=0,fixed=14.12.0; and 14 more.

**Is there a fix for CVE-2026-40169?** Yes. Magick.NET-Q16-AnyCPU (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q16-arm64 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q16-HDRI-AnyCPU (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q16-HDRI-arm64 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q16-HDRI-OpenMP-arm64 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q16-HDRI-x64 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q16-HDRI-x86 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q16-OpenMP-arm64 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q16-OpenMP-x64 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q16-x64 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q16-x86 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q8-AnyCPU (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q8-arm64 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q8-OpenMP-arm64 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q8-OpenMP-x64 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q8-x64 (NuGet): upgrade to 14.12.0 or later; Magick.NET-Q8-x86 (NuGet): upgrade to 14.12.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-40169 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-40169?** Check whether you run Dlemstra Magick.NET, ImageMagick, Magick.NET-Q16-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.

## How to fix

- Magick.NET-Q16-AnyCPU (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q16-AnyCPU --version 14.12.0
  ```

- Magick.NET-Q16-arm64 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q16-arm64 --version 14.12.0
  ```

- Magick.NET-Q16-HDRI-AnyCPU (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q16-HDRI-AnyCPU --version 14.12.0
  ```

- Magick.NET-Q16-HDRI-arm64 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q16-HDRI-arm64 --version 14.12.0
  ```

- Magick.NET-Q16-HDRI-OpenMP-arm64 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q16-HDRI-OpenMP-arm64 --version 14.12.0
  ```

- Magick.NET-Q16-HDRI-x64 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q16-HDRI-x64 --version 14.12.0
  ```

- Magick.NET-Q16-HDRI-x86 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q16-HDRI-x86 --version 14.12.0
  ```

- Magick.NET-Q16-OpenMP-arm64 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q16-OpenMP-arm64 --version 14.12.0
  ```

- Magick.NET-Q16-OpenMP-x64 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q16-OpenMP-x64 --version 14.12.0
  ```

- Magick.NET-Q16-x64 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q16-x64 --version 14.12.0
  ```

- Magick.NET-Q16-x86 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q16-x86 --version 14.12.0
  ```

- Magick.NET-Q8-AnyCPU (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q8-AnyCPU --version 14.12.0
  ```

- Magick.NET-Q8-arm64 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q8-arm64 --version 14.12.0
  ```

- Magick.NET-Q8-OpenMP-arm64 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q8-OpenMP-arm64 --version 14.12.0
  ```

- Magick.NET-Q8-OpenMP-x64 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q8-OpenMP-x64 --version 14.12.0
  ```

- Magick.NET-Q8-x64 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q8-x64 --version 14.12.0
  ```

- Magick.NET-Q8-x86 (NuGet): upgrade to 14.12.0 or later

  ```sh
  dotnet add package Magick.NET-Q8-x86 --version 14.12.0
  ```


## Technical details

A heap-based buffer overflow (CWE-122) exists in ImageMagick's YAML and JSON encoders. The vulnerability is triggered when the software attempts to write image data to YAML or JSON output formats. An attacker can provide a specially crafted image file that, when processed, results in an out-of-bounds write on the heap. This typically results in a process crash (Denial of Service). The issue is addressed in ImageMagick version 7.1.2-19 and Magick.NET version 14.12.0.

## Affected products

- ImageMagick ImageMagick < 7.1.2-19
- dlemstra Magick.NET < 14.12.0

## Identifiers

- CVE-2026-40169
- GHSA-5592-p365-24xh

## Timeline

- 2026-04-13: advisory: NVD publication date
- 2026-04-14: disclosed: GitHub Advisory published

## References

- [https://api.github.com/users/zer0matt](https://api.github.com/users/zer0matt)
- [https://github.com/zer0matt](https://github.com/zer0matt)
- [https://api.github.com/users/zer0matt/gists%7B/gist_id%7D](https://api.github.com/users/zer0matt/gists%7B/gist_id%7D)
- [https://api.github.com/users/zer0matt/repos](https://api.github.com/users/zer0matt/repos)
- [https://avatars.githubusercontent.com/u/28620328?v=4](https://avatars.githubusercontent.com/u/28620328?v=4)
- [https://api.github.com/users/zer0matt/events%7B/privacy%7D](https://api.github.com/users/zer0matt/events%7B/privacy%7D)

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- [ImageMagick memory leak in XMP profile handling](https://junglewise.ai/threats/cve-2026-116155-imagemagick-before-6-9-13-58-and-7-x-before-7-1-2-33-contains-a)
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- [ImageMagick memory leak in MAT decoder](https://junglewise.ai/threats/cve-2026-116152-imagemagick-before-7-1-2-33-contains-a-memory-leak-vulnerability)
- [ImageMagick stack buffer overflow in bzip2 decompression](https://junglewise.ai/threats/cve-2026-116149-imagemagick-before-6-9-13-58-and-7-x-before-7-1-2-33-contains-a)