ImageMagick is an open source software suite for displaying, converting, and editing raster image files. In ImageMagick versions prior to 7.1.2-7 and 6.9.13-32, an integer overflow vulnerability exists in the BMP decoder on 32-bit systems. The vulnerability occurs in coders/bmp.c when calculating the extent value by multiplying image columns by bits per pixel. On 32-bit systems with size_t of 4 bytes, a malicious BMP file with specific dimensions can cause this multiplication to overflow and wrap to zero. The overflow check added to address CVE-2025-57803 is placed after the overflow occurs, making it ineffective. A specially crafted 58-byte BMP file with width set to 536,870,912 and 32 bits per pixel can trigger this overflow, causing the bytes_per_line calculation to become zero. This vulnerability only affects 32-bit builds of ImageMagick where default resource limits for width, height, and area have been manually increased beyond their defaults. 64-bit systems with size_t of 8 bytes are not vulnerable, and systems using default ImageMagick resource limits are not vulnerable. The vulnerability is fixed in versions 7.1.2-7 and 6.9.13-32.

Affected: NuGet: Magick.NET-Q16-AnyCPU, NuGet: Magick.NET-Q16-HDRI-AnyCPU, NuGet: Magick.NET-Q16-HDRI-x86, NuGet: Magick.NET-Q16-x86, NuGet: Magick.NET-Q8-AnyCPU, NuGet: Magick.NET-Q8-x86

## Summary

CVE-2025-57803 claims to be patched in ImageMagick 7.1.2-2, but **the fix is incomplete and ineffective**. The latest version **7.1.2-5 remains vulnerable** to the same integer overflow attack.

The patch added `BMPOverflowCheck()` but placed it **after** the overflow occurs, making it useless. A malicious 58-byte BMP file can trigger AddressSanitizer crashes and DoS.

**Affected Versions:** - ImageMagick < 7.1.2-2 (originally reported) - **ImageMagick 7.1.2-2 through 7.1.2-5 (incomplete patch)**

**Platform and Configuration Requirements:** - 32-bit systems ONLY (i386, i686, armv7l, etc.) - Requires `size_t = 4 bytes`. (64-bit systems are **NOT vulnerable** (size_t = 8 bytes)) - Requires modified resource limits: The default `width`, `height`, and `area` limits must have been manually increased (Systems using default ImageMagick resource limits are **NOT vulnerable**).

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## Details(Root Cause Analysis)

### Vulnerable Code Location

**File:** `coders/bmp.c` **Lines:** 1120-1122 (in version 7.1.2-5)

### The Incomplete Patch

```c // Line 1120: Integer overflow happens HERE extent = image->columns * bmp_info.bits_per_pixel; // OVERFLOW!

// Line 1121: Uses already-overflowed value bytes_per_line = 4*((extent+31)/32);

// Line 1122: Checks the RESULT, not the multiplication if (BMPOverflowCheck(bytes_per_line, image->rows) != MagickFalse) ThrowReaderException(CorruptImageError, "InsufficientImageDataInFile"); ```

### Why the Patch Fails

**Attack Vecto…

Affected: openEuler:24.03-LTS: 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 contains an integer overflow vulnerability in the BMP decoder. An attacker can exploit this vulnerability by providing a specially crafted BMP file, leading to buffer overflow or denial of service.(CVE-2025-62171)

ImageMagick-7.1.2.7-1.1 on GA media

ImageMagick: ImageMagick vulnerable to denial of service via integer overflow in BMP decoder on 32-bit systems ImageMagick: ImageMagick: Arbitrary code execution via a crafted XBM image file

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, Ubuntu:25.10: imagemagick, Ubuntu:26.04:LTS: imagemagick

ImageMagick is an open source software suite for displaying, converting, and editing raster image files. In ImageMagick versions prior to 7.1.2-7 and 6.9.13-32, an integer overflow vulnerability exists in the BMP decoder on 32-bit systems. The vulnerability occurs in coders/bmp.c when calculating the extent value by multiplying image columns by bits per pixel. On 32-bit systems with size_t of 4 bytes, a malicious BMP file with specific dimensions can cause this multiplication to overflow and wrap to zero. The overflow check added to address CVE-2025-57803 is placed after the overflow occurs, making it ineffective. A specially crafted 58-byte BMP file with width set to 536,870,912 and 32 bits per pixel can trigger this overflow, causing the bytes_per_line calculation to become zero. This vulnerability only affects 32-bit builds of ImageMagick where default resource limits for width, height, and area have been manually increased beyond their defaults. 64-bit systems with size_t of 8 bytes are not vulnerable, and systems using default ImageMagick resource limits are not vulnerable. The vulnerability is fixed in versions 7.1.2-7 and 6.9.13-32.

Ein entfernter, authentisierter Angreifer kann eine Schwachstelle in ImageMagick ausnutzen, um einen Denial of Service Angriff durchzuführen.