# CVE-2026-70651: libvips heap buffer over-read in ImageMagick fallback path

Source: https://junglewise.ai/threats/cve-2026-70651-libvips-heap-buffer-over-read-in-imagemagick-fallback-path  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-20. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-70651 · Severity: info · Published 2026-08-20

libvips is a fast image processing library used to handle and transform images across many applications. When built without libtiff support but with ImageMagick fallback enabled, the library can be crashed by a specially crafted multi-page TIFF image, potentially disrupting services that depend on it for image processing.

Technologies: [Libvips](https://junglewise.ai/threats/technologies/libvips). Vendors: [Libvips](https://junglewise.ai/threats/vendors/libvips).

## Quick answers

**Is CVE-2026-70651 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-70651 being exploited in the wild.

**How severe is CVE-2026-70651?** Informational severity, published 20 August 2026.

**Which products and versions are affected?** Libvips prior to 8.18.3.

**Is there a fix for CVE-2026-70651?** A patch was published on 2026-05-14: Fix merged in commit 05719ca3d5852acdeb6714de2e8e769c9a5d2c11 for version 8.18.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-70651 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-70651?** Check whether you run Libvips 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

This is a heap buffer over-read vulnerability in the ImageMagick fallback loader (VipsForeignLoadMagick) found in libvips/foreign/magick6load.c and libvips/foreign/magick7load.c. The vulnerable code multiplies per-page Ysize by the number of frames (n_frames) without overflow checking, leading to an integer overflow and undersized heap buffer allocation. An attacker can provide a crafted multi-page TIFF file that triggers this overflow when processed by libvips without native libtiff support, resulting in a heap buffer over-read and process crash (denial of service). The vulnerability affects versions prior to 8.18.3 and is fixed in that version. Most package-manager distributions include libtiff support and do not use this vulnerable fallback path.

## Affected products

- libvips libvips prior to 8.18.3

## Timeline

- 2026-08-20: disclosed: CVE-2026-70651 published
- 2026-05-14: patched: Fix merged in commit 05719ca3d5852acdeb6714de2e8e769c9a5d2c11 for version 8.18.3

## References

- [https://github.com/libvips/libvips/commit/05719ca3d5852acdeb6714de2e8e769c9a5d2c11](https://github.com/libvips/libvips/commit/05719ca3d5852acdeb6714de2e8e769c9a5d2c11)
- [https://github.com/libvips/libvips/pull/5040](https://github.com/libvips/libvips/pull/5040)

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