CVE-2026-25576: ImageMagick Buffer Overflow Vulnerability

CVE-2026-25576 Overview

ImageMagick, a widely-used free and open-source software suite for editing and manipulating digital images, contains a heap buffer over-read vulnerability affecting multiple raw image format handlers. This vulnerability exists in versions prior to 7.1.2-15 and 6.9.13-40, where processing images with -extract dimensions larger than -size dimensions causes out-of-bounds memory reads from a heap-allocated buffer.

Critical Impact

Attackers can potentially exploit this vulnerability to read sensitive information from memory by crafting malicious image files that trigger the out-of-bounds read condition, potentially leading to information disclosure.

Affected Products

• ImageMagick versions prior to 7.1.2-15
• ImageMagick versions prior to 6.9.13-40
• Magick.NET versions prior to 14.10.3

Discovery Timeline

• 2026-02-24 - CVE-2026-25576 published to NVD
• 2026-02-24 - Last updated in NVD database

Technical Details for CVE-2026-25576

Vulnerability Analysis

This vulnerability (CWE-122: Heap-based Buffer Overflow) manifests in multiple raw image format coders within ImageMagick, including coders/gray.c and coders/raw.c. The flaw occurs during image processing when the -extract parameter specifies dimensions that exceed those defined by the -size parameter. When this condition is met, the application attempts to read beyond the boundaries of a heap-allocated buffer, resulting in an out-of-bounds memory read operation.

The vulnerability requires local access and involves high attack complexity, as the attacker must craft a specific image file with precise dimension parameters to trigger the vulnerable code path. While the vulnerability does not impact system integrity or availability, successful exploitation could lead to disclosure of sensitive information stored in adjacent memory regions.

Root Cause

The root cause lies in insufficient boundary validation in the raw pixel data reading routines. When extracting a region from a raw image, the coders fail to properly validate that the extraction dimensions do not exceed the source image size, leading to reads beyond the allocated buffer boundaries. The fix introduces proper column bounds tracking by adding a columns variable to the affected coders to ensure safe memory access.

Attack Vector

An attacker would need to craft a malicious raw image file and convince a victim to process it with ImageMagick using specific -extract and -size parameters where the extract dimensions exceed the size dimensions. This could occur through:

1. Uploading malicious images to web applications that use ImageMagick for processing
2. Sending crafted image files via email or messaging platforms
3. Placing malicious images on file shares or content management systems

The patch introduces proper bounds checking by tracking the columns variable to prevent reading beyond allocated buffer limits:

    length;
 
  ssize_t
+    columns,
    count,
    y;

Source: ImageMagick Security Commit

Detection Methods for CVE-2026-25576

Indicators of Compromise

• Unexpected crashes or memory access violations in ImageMagick processes
• ImageMagick error logs showing segmentation faults during raw image processing
• Anomalous image processing requests with mismatched -extract and -size parameters
• System logs indicating heap corruption or memory read errors in convert, mogrify, or related ImageMagick binaries

Detection Strategies

• Monitor for ImageMagick processes with command-line arguments containing both -extract and -size parameters
• Implement file integrity monitoring on ImageMagick binaries to detect tampering
• Deploy application-level monitoring to detect unusual image processing patterns
• Use memory sanitizers (ASan/MSan) in development environments to catch out-of-bounds reads

Monitoring Recommendations

• Enable verbose logging for ImageMagick operations to capture processing parameters
• Monitor system resource utilization for anomalous memory access patterns during image processing
• Implement centralized logging for all image processing activities across your infrastructure
• Set up alerts for repeated failures or crashes in image processing workflows

How to Mitigate CVE-2026-25576

Immediate Actions Required

• Upgrade ImageMagick to version 7.1.2-15 or later (for 7.x branch)
• Upgrade ImageMagick to version 6.9.13-40 or later (for 6.x branch)
• Upgrade Magick.NET to version 14.10.3 or later if using the .NET wrapper
• Review and restrict ImageMagick policy.xml to limit raw image format processing if immediate patching is not possible

Patch Information

Security patches are available through the official ImageMagick repositories. The fix has been committed with hash 077b42643212d7da8c1a4f6b2cd0067ebca8ec0f and is included in versions 7.1.2-15 and 6.9.13-40. For detailed patch information, refer to the GitHub Security Advisory and the Magick.NET Release 14.10.3.

Workarounds

• Disable processing of raw image formats in ImageMagick's policy.xml configuration file
• Implement input validation to reject image files with suspicious dimension parameters
• Run ImageMagick in a sandboxed environment to limit potential impact of exploitation
• Use application-level checks to validate -extract dimensions do not exceed -size dimensions before processing

# Configuration example - Restrict raw format processing in policy.xml
# Add to /etc/ImageMagick-7/policy.xml or equivalent location
<policy domain="coder" rights="none" pattern="GRAY" />
<policy domain="coder" rights="none" pattern="RAW" />
<policy domain="coder" rights="none" pattern="RGB" />