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: NuGet: Magick.NET-Q16-x64, NuGet: Magick.NET-Q8-x64, NuGet: Magick.NET-Q16-HDRI-x64, NuGet: Magick.NET-Q8-OpenMP-x64, NuGet: Magick.NET-Q16-HDRI-OpenMP-x64, NuGet: Magick.NET-Q16-OpenMP-x64, NuGet: Magick.NET-Q8-arm64, NuGet: Magick.NET-Q16-arm64, NuGet: Magick.NET-Q16-OpenMP-arm64, NuGet: Magick.NET-Q8-OpenMP-arm64 and 2 more

**Reporter:** Lumina Mescuwa **Product:** ImageMagick 7 (MagickCore) **Component:** `MagickCore/blob.c` (Blob I/O - BlobStream) **Tested:** 7.1.2-0 (source tag) and 7.1.2-1 (Homebrew), macOS arm64, clang-17, Q16-HDRI **Impact:** Heap out-of-bounds **WRITE** (attacker-controlled bytes at attacker-chosen offset) → memory corruption; potential code execution

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## Executive Summary

For memory-backed blobs (**BlobStream**), [`SeekBlob()`](https://github.com/ImageMagick/ImageMagick/blob/3fcd081c0278427fc0e8ac40ef75c0a1537792f7/MagickCore/blob.c#L5106-L5134) permits advancing the stream **offset** beyond the current end without increasing capacity. The subsequent [`WriteBlob()`](https://github.com/ImageMagick/ImageMagick/blob/3fcd081c0278427fc0e8ac40ef75c0a1537792f7/MagickCore/blob.c#L5915-L5938) 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.

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## Affected Scope

- **Versions confirmed:** 7.1.2-0, 7.1.2-1 - **Architectures:** Observed on macOS arm64; architecture-agnostic on LP64 - Paths: MagickCore blob subsystem — **BlobStream** ([`SeekBlob()`](https://github.com/ImageMagick/ImageMagick/blob/3fcd081c0278427fc0e8ac40ef75c0a1537792f7/MagickCore/blob.c#L5106-L5134) and [`WriteBlob()`](ht…

Affected: openEuler:20.03-LTS-SP4: ImageMagick

Use ImageMagick to create, edit, compose, or convert bitmap images. It can read and write images in a variety of formats (over 200) including PNG, JPEG, GIF, HEIC, TIFF, DPX, EXR, WebP, Postscript, PDF, and SVG. Use ImageMagick to resize, flip, mirror, rotate, distort, shear and transform images, adjust image colors, apply various special effects, or draw text, lines, polygons, ellipses and Bézier curves. Security Fix(es):

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.(CVE-2025-57807)

ImageMagick-7.1.2.3-1.1 on GA media

Security update for ImageMagick

Affected: Ubuntu:Pro:14.04:LTS: imagemagick, Ubuntu:Pro:16.04:LTS: imagemagick, Ubuntu:Pro:18.04:LTS: imagemagick, Ubuntu:Pro:20.04:LTS: imagemagick, Ubuntu:Pro:22.04:LTS: imagemagick, Ubuntu:Pro:24.04:LTS: imagemagick

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.

Ein entfernter, anonymer Angreifer kann eine Schwachstelle in ImageMagick ausnutzen, um eine Speicherbeschädigung zu verursachen und möglicherweise beliebigen Code auszuführen.