CVE-2026-53461: ImageMagick Buffer Overflow Vulnerability

CVE-2026-53461 Overview

CVE-2026-53461 is an out-of-bounds heap write vulnerability in ImageMagick, the open-source image editing and manipulation suite. The flaw resides in the ICON decoder, where an incorrect loop boundary allows writes beyond an allocated heap buffer. Processing a crafted ICON file triggers the condition and causes the application to crash. The issue affects ImageMagick versions prior to 6.9.13-50 and 7.1.2-25. The vulnerability is tracked under [CWE-787] (Out-of-bounds Write) and is remotely exploitable when ImageMagick processes attacker-supplied images without user interaction.

Critical Impact

Remote attackers can crash applications and services that use ImageMagick to decode ICON files, producing a denial-of-service condition across web platforms, image pipelines, and document processors that embed the library.

Affected Products

• ImageMagick versions prior to 6.9.13-50 (6.x branch)
• ImageMagick versions prior to 7.1.2-25 (7.x branch)
• Applications and services that embed vulnerable ImageMagick releases for ICON decoding

Discovery Timeline

• 2026-06-10 - CVE-2026-53461 published to the National Vulnerability Database
• 2026-06-10 - Last updated in NVD database

Technical Details for CVE-2026-53461

Vulnerability Analysis

The vulnerability exists in the ICON decoder component of ImageMagick. An incorrect loop iteration count causes the decoder to write past the end of a heap-allocated buffer while parsing ICON image data. The out-of-bounds write corrupts adjacent heap memory and terminates the process abnormally. Because ImageMagick is widely embedded in web applications, content management systems, and automated image pipelines, any service that accepts user-supplied images and routes them to the ICON decoder is exposed. Successful exploitation requires only that a crafted file reach the vulnerable code path, which typically occurs when applications auto-detect image formats during upload or conversion.

Root Cause

The root cause is a loop control error in the ICON decoder. The loop continues to iterate beyond the bounds of the destination buffer, performing writes to memory the allocation does not own. This is a classic [CWE-787] Out-of-bounds Write defect where buffer size and iteration count are not consistently validated against one another.

Attack Vector

An attacker delivers a malformed ICON file to a system that uses ImageMagick. Common delivery vectors include file upload endpoints, profile picture processors, document conversion services, and thumbnail generators. No authentication or user interaction is required for the decoder to be invoked, since most image processing happens server-side immediately upon receipt. The result is a process crash and denial of service for the application consuming the library.

No verified public proof-of-concept code is available at this time. Technical details are described in the GitHub Security Advisory GHSA-g22q-f7gc-5jhr.

Detection Methods for CVE-2026-53461

Indicators of Compromise

• Repeated crashes or abnormal terminations of processes invoking convert, magick, or MagickCore libraries
• ICON (.ico) file uploads followed by service restarts or worker process recycling
• Core dumps or segmentation faults referencing the ICON decoder code path

Detection Strategies

• Inventory all hosts and containers running ImageMagick and compare installed versions against 6.9.13-50 and 7.1.2-25
• Monitor application logs for ImageMagick exit codes, signal terminations, and decoder error messages tied to ICON parsing
• Inspect web application firewall (WAF) telemetry for ICON file uploads with anomalous file sizes or malformed headers

Monitoring Recommendations

• Enable verbose ImageMagick logging in non-production environments to capture decoder errors and stack traces
• Track child process crash rates for image-processing workers and alert on statistical deviations
• Correlate file upload events with subsequent process termination events to identify exploitation attempts

How to Mitigate CVE-2026-53461

Immediate Actions Required

• Upgrade ImageMagick to version 6.9.13-50 or 7.1.2-25 or later on all systems
• Identify embedded ImageMagick instances inside container images, third-party applications, and language bindings such as imagemagick, Wand, and RMagick
• Restrict the list of enabled coders in policy.xml to those required by the application until patches are deployed

Patch Information

The ImageMagick maintainers fixed the incorrect loop in the ICON decoder and released the corrected code in versions 6.9.13-50 and 7.1.2-25. Patch details are published in the ImageMagick GitHub Security Advisory. Rebuild any downstream packages, container images, or statically linked applications that bundle ImageMagick after applying the update.

Workarounds

• Disable the ICON coder in the ImageMagick policy file by adding a <policy domain="coder" rights="none" pattern="ICON" /> rule until patching is complete
• Validate uploaded file MIME types and reject ICON files at the application layer where the format is not required
• Run ImageMagick processing in isolated, resource-limited sandboxes to contain crash impact and prevent cascading failures

# Configuration example: disable the ICON coder in /etc/ImageMagick-7/policy.xml
<policymap>
  <policy domain="coder" rights="none" pattern="ICON" />
  <policy domain="coder" rights="none" pattern="CUR" />
</policymap>

# Verify installed version
magick -version | head -n 1