ImageMagick affected by divide-by-zero in ThumbnailImage via montage -geometry ":" leads to crash

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

3.7 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

EPSS

• CVE-2025-55212: 1.00% estimated exploitation activity in the next 30 days; percentile 62.73 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Passing a geometry string containing only a colon (":") to montage -geometry leads GetGeometry() to set width/height to 0. Later, ThumbnailImage() divides by these zero dimensions, triggering a crash (SIGFPE/abort), resulting in a denial of service. Details Root Cause 1. montage -geometry ":" ... reaches MagickCore/geometry.c:GetGeometry(). 2. StringToDouble/InterpretLocaleValue parses ":" as 0.0; then: https://github.com/ImageMagick/ImageMagick/blob/0ba1b587be17543b664f7ad538e9e51e0da59d17/MagickCore/geometry.c#L355 WidthValue (and/or HeightValue) is set with a zero dimension. 3. In MagickCore/resize.c:ThumbnailImage(), the code computes: https://github.com/ImageMagick/ImageMagick/blob/0ba1b587be17543b664f7ad538e9e51e0da59d17/MagickCore/resize.c#L4625-L4629 causing a division by zero and immediate crash. The issue is trivially triggerable without external input files (e.g., using xc:white). Reproduction Environment Steps Observed result PoC No external file required; the…

Published by the source

26 Aug 2025, 15:27 UTC

Last modified by the source

3 Nov 2025, 21:35 UTC

Source last checked

26 Oct 2026, 17:04 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-fh55-q5pj-pxgw

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# Patch Next advisory brief: CVE-2025-55212

Advisory: ImageMagick affected by divide-by-zero in ThumbnailImage via montage -geometry ":" leads to crash
IDs: CVE-2025-55212, GHSA-fh55-q5pj-pxgw
Record: https://patchnext.com/advisories/cve-2025-55212 (revision 1, source checked 26 Oct 2026, 17:04 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 3.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: magick.net-q8-arm64 14.8.1; magick.net-q8-x86 14.8.1; magick.net-q16-hdri-anycpu 14.8.1; magick.net-q16-openmp-x64 14.8.1; magick.net-q16-anycpu 14.8.1; magick.net-q16-hdri-x86 14.8.1; magick.net-q16-hdri-openmp-arm64 14.8.1; magick.net-q16-hdri-arm64 14.8.1; magick.net-q16-x86 14.8.1; magick.net-q8-openmp-x64 14.8.1; magick.net-q16-hdri-openmp-x64 14.8.1; magick.net-q16-openmp-arm64 14.8.1; magick.net-q16-x64 14.8.1; magick.net-q8-x64 14.8.1; magick.net-q8-openmp-arm64 14.8.1; magick.net-q8-anycpu 14.8.1; magick.net-q16-arm64 14.8.1; magick.net-q16-hdri-x64 14.8.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- NuGet magick.net-q8-arm64: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q8-x86: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-hdri-anycpu: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-openmp-x64: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-anycpu: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-hdri-x86: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-hdri-openmp-arm64: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-hdri-arm64: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-x86: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q8-openmp-x64: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-hdri-openmp-x64: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-openmp-arm64: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-x64: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q8-x64: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q8-openmp-arm64: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q8-anycpu: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-arm64: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q16-hdri-x64: affected < 14.8.1; fixed in 14.8.1

## Suggested inspection (read-only)
- NuGet magick.net-q8-arm64: check the installed version with your package manager.
- NuGet magick.net-q8-x86: check the installed version with your package manager.
- NuGet magick.net-q16-hdri-anycpu: check the installed version with your package manager.
- NuGet magick.net-q16-openmp-x64: check the installed version with your package manager.
- NuGet magick.net-q16-anycpu: check the installed version with your package manager.
- NuGet magick.net-q16-hdri-x86: check the installed version with your package manager.
- NuGet magick.net-q16-hdri-openmp-arm64: check the installed version with your package manager.
- NuGet magick.net-q16-hdri-arm64: check the installed version with your package manager.
- NuGet magick.net-q16-x86: check the installed version with your package manager.
- NuGet magick.net-q8-openmp-x64: check the installed version with your package manager.
- NuGet magick.net-q16-hdri-openmp-x64: check the installed version with your package manager.
- NuGet magick.net-q16-openmp-arm64: check the installed version with your package manager.
- NuGet magick.net-q16-x64: check the installed version with your package manager.
- NuGet magick.net-q8-x64: check the installed version with your package manager.
- NuGet magick.net-q8-openmp-arm64: check the installed version with your package manager.
- NuGet magick.net-q8-anycpu: check the installed version with your package manager.
- NuGet magick.net-q16-arm64: check the installed version with your package manager.
- NuGet magick.net-q16-hdri-x64: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on magick.net-q8-arm64, magick.net-q8-x86, magick.net-q16-hdri-anycpu, magick.net-q16-openmp-x64, magick.net-q16-anycpu, magick.net-q16-hdri-x86, magick.net-q16-hdri-openmp-arm64, magick.net-q16-hdri-arm64, magick.net-q16-x86, magick.net-q8-openmp-x64, magick.net-q16-hdri-openmp-x64, magick.net-q16-openmp-arm64, magick.net-q16-x64, magick.net-q8-x64, magick.net-q8-openmp-arm64, magick.net-q8-anycpu, magick.net-q16-arm64, magick.net-q16-hdri-x64.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-fh55-q5pj-pxgw (GitHub-reviewed advisory GHSA-fh55-q5pj-pxgw lists affected ranges: NuGet magick.net-q16-anycpu >=0 =0 =0 =0 =0 =0 =0 =0 =0 <14.8.1; NuGet…)

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