ImageMagick (WriteBMPImage): 32-bit integer overflow when writing BMP scanline stride → heap buffer overflow

Exploitation

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

CVSS

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

EPSS

• CVE-2025-57803: 0.91% estimated exploitation activity in the next 30 days; percentile 59.98 (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 A 32-bit integer overflow in the BMP encoder’s scanline-stride computation collapses bytesperline (stride) to a tiny value while the per-row writer still emits 3 × width bytes for 24-bpp images. The row base pointer advances using the (overflowed) stride, so the first row immediately writes past its slot and into adjacent heap memory with attacker-controlled bytes. This is a classic, powerful primitive for heap corruption in common auto-convert pipelines. - Impact: Attacker-controlled heap out-of-bounds (OOB) write during conversion to BMP. - Surface: Typical upload → normalize/thumbnail → magick ... out.bmp workers. - 32-bit: Vulnerable (reproduced with ASan). - 64-bit: Safe from this specific integer overflow (IOF) by arithmetic, but still add product/size guards. - Proposed severity: Critical 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H). --- Scope & Affected Builds - Project: ImageMagick (BMP writer path, WriteBMPImage in coders/bmp.c). - Commit under test:…

Published by the source

26 Aug 2025, 16:07 UTC

Last modified by the source

3 Nov 2025, 21:34 UTC

Source last checked

26 Oct 2026, 17:04 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-mxvv-97wh-cfmm

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# Patch Next advisory brief: CVE-2025-57803

Advisory: ImageMagick (WriteBMPImage): 32-bit integer overflow when writing BMP scanline stride → heap buffer overflow
IDs: CVE-2025-57803, GHSA-mxvv-97wh-cfmm
Record: https://patchnext.com/advisories/cve-2025-57803 (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: High (CVSS 7.5)
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 14.8.1; magick.net-q16-hdri-anycpu 14.8.1; magick.net-q16-anycpu 14.8.1; magick.net-q16-hdri-x86 14.8.1; magick.net-q16-x86 14.8.1; magick.net-q8-anycpu 14.8.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- 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-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-x86: affected < 14.8.1; fixed in 14.8.1
- NuGet magick.net-q8-anycpu: affected < 14.8.1; fixed in 14.8.1

## 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-mxvv-97wh-cfmm (GitHub-reviewed advisory GHSA-mxvv-97wh-cfmm lists affected ranges: NuGet magick.net-q16-anycpu >=0 =0 =0 =0 =0 =0 <14.8.1)

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