ImageMagick has a heap overflow caused by integer overflow/wraparound in viff encoder on 32-bit builds

Exploitation

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

CVSS

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

EPSS

• CVE-2026-33900: 0.43% estimated exploitation activity in the next 30 days; percentile 37.73 (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.

ImageMagick is free and open-source software used for editing and manipulating digital images. In versions below both 7.1.2-19 and 6.9.13-44, the viff encoder contains an integer truncation/wraparound issue on 32-bit builds that could trigger an out of bounds heap write, potentially causing a crash. This issue has been fixed in versions 6.9.13-44 and 7.1.2-19.

Published by the source

13 Apr 2026, 19:09 UTC

Last modified by the source

24 Apr 2026, 20:47 UTC

Source last checked

26 Oct 2026, 17:04 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-v67w-737x-v2c9

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# Patch Next advisory brief: CVE-2026-33900

Advisory: ImageMagick has a heap overflow caused by integer overflow/wraparound in viff encoder on 32-bit builds
IDs: CVE-2026-33900, GHSA-v67w-737x-v2c9
Record: https://patchnext.com/advisories/cve-2026-33900 (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: Medium (CVSS 5.9)
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-x86 14.12.0; magick.net-q16-hdri-anycpu 14.12.0; magick.net-q16-anycpu 14.12.0; magick.net-q16-hdri-x86 14.12.0; magick.net-q16-x86 14.12.0; magick.net-q8-anycpu 14.12.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- NuGet magick.net-q8-x86: affected < 14.12.0; fixed in 14.12.0
- NuGet magick.net-q16-hdri-anycpu: affected < 14.12.0; fixed in 14.12.0
- NuGet magick.net-q16-anycpu: affected < 14.12.0; fixed in 14.12.0
- NuGet magick.net-q16-hdri-x86: affected < 14.12.0; fixed in 14.12.0
- NuGet magick.net-q16-x86: affected < 14.12.0; fixed in 14.12.0
- NuGet magick.net-q8-anycpu: affected < 14.12.0; fixed in 14.12.0

## Suggested inspection (read-only)
- 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-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-x86: check the installed version with your package manager.
- NuGet magick.net-q8-anycpu: 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-x86, magick.net-q16-hdri-anycpu, magick.net-q16-anycpu, magick.net-q16-hdri-x86, magick.net-q16-x86, magick.net-q8-anycpu.
- 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-v67w-737x-v2c9 (GitHub-reviewed advisory GHSA-v67w-737x-v2c9 lists affected ranges: NuGet magick.net-q16-anycpu >=0 =0 =0 =0 =0 =0 <14.12.0)

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