Description
ImageMagick is free and open-source software used for editing and manipulating digital images. ImageMagick versions lower than 14.8.2 include insecure functions: SeekBlob(), which permits advancing the stream offset beyond the current end without increasing capacity, and WriteBlob(), which then expands by quantum + length (amortized) instead of offset + length, and copies to data + offset. When offset ≫ extent, the copy targets memory beyond the allocation, producing a deterministic heap write on 64-bit builds. No 2⁶⁴ arithmetic wrap, external delegates, or policy settings are required. This is fixed in version 14.8.2.
Affected products
imagemagick: imagemagick
References4
- github.com/ImageMagick/ImageMagick/security/advisories/GHSA-23h… ExploitMitigationVendor Advisory
- github.com/ImageMagick/ImageMagick/security/advisories/GHSA-23h… ExploitMitigationVendor Advisory
- github.com/ImageMagick/ImageMagick/commit/077a417a19a5ea8c85559… Patch
- lists.debian.org/debian-lts-announce/2025/09/msg00012.html
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 23 · as of 8 November 2026
- CWE
- CWE-122CWE-131CWE-787
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