CVE-2025-55154: ImageMagick Buffer Overflow Vulnerability

CVE-2025-55154 Overview

CVE-2025-55154 is an Integer Overflow vulnerability affecting ImageMagick, the widely-used free and open-source software for editing and manipulating digital images. The vulnerability exists in the ReadOneMNGImage function within coders/png.c, where magnified size calculations are performed unsafely. These calculations can overflow, leading to memory corruption that could potentially be exploited by attackers.

Critical Impact

An attacker can craft a malicious MNG image file that, when processed by ImageMagick, triggers an integer overflow in magnification calculations, resulting in memory corruption. This could lead to arbitrary code execution with the privileges of the application processing the image.

Affected Products

• ImageMagick versions prior to 6.9.13-27
• ImageMagick versions prior to 7.1.2-1

Discovery Timeline

• 2025-08-13 - CVE-2025-55154 published to NVD
• 2025-11-03 - Last updated in NVD database

Technical Details for CVE-2025-55154

Vulnerability Analysis

This vulnerability is classified as CWE-190 (Integer Overflow or Wraparound). The flaw resides in the MNG (Multiple-image Network Graphics) image parsing code, specifically within the ReadOneMNGImage function in coders/png.c. When processing MNG images that contain magnification parameters, the code performs size calculations without proper bounds checking.

The vulnerability requires local access and user interaction to exploit—typically by convincing a user to open a maliciously crafted MNG image file. Once triggered, the integer overflow corrupts memory allocations, potentially allowing an attacker to achieve arbitrary code execution with high impact to confidentiality, integrity, and availability.

Root Cause

The root cause of CVE-2025-55154 is the absence of proper overflow checks in the magnification size calculations within the MNG image decoder. When large magnification values are specified in a crafted MNG file, the multiplication operations used to calculate buffer sizes can wrap around, resulting in undersized memory allocations. Subsequent operations then write beyond the allocated buffer boundaries, corrupting adjacent memory regions.

Attack Vector

The attack vector is local, requiring an attacker to deliver a specially crafted MNG image file to the victim. This could be achieved through various means:

1. Email attachments containing malicious MNG files
2. Web applications that process user-uploaded images using ImageMagick
3. Document processors or content management systems that invoke ImageMagick for image manipulation
4. Thumbnail generation services that automatically process uploaded images

When a vulnerable ImageMagick instance processes the malicious MNG file, the integer overflow in ReadOneMNGImage causes memory corruption. The vulnerability exploits the mathematical overflow that occurs when magnification dimensions are multiplied without proper bounds validation.

Detection Methods for CVE-2025-55154

Indicators of Compromise

• Unexpected crashes or segmentation faults in ImageMagick processes when processing MNG files
• Unusual memory consumption spikes during image processing operations
• Core dumps containing references to ReadOneMNGImage or coders/png.c in stack traces
• Detection of MNG files with abnormally large magnification parameters

Detection Strategies

• Monitor ImageMagick process crashes and analyze core dumps for stack traces involving ReadOneMNGImage
• Implement file integrity monitoring on ImageMagick binaries to detect unauthorized modifications
• Deploy static analysis rules to identify MNG files with suspicious magnification values
• Use SentinelOne's behavioral AI to detect anomalous memory access patterns during image processing

Monitoring Recommendations

• Enable verbose logging for ImageMagick operations to capture file processing details
• Set up alerting for ImageMagick process crashes or unexpected terminations
• Monitor for unusual file uploads containing MNG format images in web applications
• Implement memory usage thresholds for image processing services

How to Mitigate CVE-2025-55154

Immediate Actions Required

• Update ImageMagick to version 6.9.13-27 or later for the 6.x branch
• Update ImageMagick to version 7.1.2-1 or later for the 7.x branch
• Review and restrict ImageMagick policy.xml to disable MNG coders if not required
• Audit systems to identify all instances of ImageMagick installations

Patch Information

The ImageMagick maintainers have released patches in versions 6.9.13-27 and 7.1.2-1 that address this integer overflow vulnerability. Users should update to these versions or later to receive the security fix. For detailed information about the vulnerability and patch, refer to the GitHub Security Advisory GHSA-qp29-wxp5-wh82.

Additional resources:

• Debian LTS Security Announcement
• Google BigSleep Research

Workarounds

• Disable MNG format support by modifying ImageMagick's policy.xml configuration file
• Implement strict input validation to reject MNG files before processing
• Run ImageMagick in a sandboxed environment with restricted memory and process capabilities
• Use application-level filtering to block MNG file uploads in web applications

# Configuration example - Disable MNG format in ImageMagick policy.xml
# Add the following to /etc/ImageMagick-6/policy.xml or /etc/ImageMagick-7/policy.xml

<policy domain="coder" rights="none" pattern="MNG" />
<policy domain="coder" rights="none" pattern="PNG" />

# Alternatively, limit memory resources to reduce exploit impact
<policy domain="resource" name="memory" value="256MiB"/>
<policy domain="resource" name="map" value="512MiB"/>
<policy domain="resource" name="disk" value="1GiB"/>