CVE-2025-69204: 
ImageMagick vulnerability analysis and mitigation

CVE-2025-69204 is an integer overflow vulnerability in ImageMagick's WriteSVGImage function that leads to a buffer overflow and Denial of Service (DoS). It affects all ImageMagick versions prior to 7.1.2-12 and is triggered when converting a malicious MVG file to SVG format. The vulnerability was published on December 30, 2025, and assigned a CVSS v3.1 base score of 7.5 (High) by NVD, though the GitHub advisory rates it as Moderate (5.3) (GitHub Advisory, Feedly).

The root cause is an integer overflow (CWE-190) in coders/svg.c at line 4723, where the variable number_attributes was declared as a signed int instead of an unsigned size_t. An attacker can craft a malicious MVG file with a large number of alphabetic characters in a path token, causing number_attributes to grow very large. When the expression 6 * BezierQuantum * number_attributes is computed, it overflows the signed integer, producing a negative or incorrect value. This causes number_points to be incremented to a much smaller value than intended (e.g., 1904 instead of ~4.3 billion), leading to an undersized ResizeQuantumMemory allocation and subsequent buffer overflow when primitive_info is accessed (GitHub Advisory, Fix Commit).

Successful exploitation causes a buffer overflow or null pointer dereference in the ImageMagick process, resulting in application crash and Denial of Service. There is no identified confidentiality or integrity impact — the vulnerability affects only availability. Systems that automatically process user-supplied or externally sourced image files (e.g., web applications using ImageMagick for image conversion) are at elevated risk of service disruption (GitHub Advisory).

1. Craft malicious MVG file: Create an MVG (Magick Vector Graphics) file containing a PathPrimitive element with a token string composed of a very large number of alphabetic characters, designed to maximize the value of number_attributes during parsing.
2. Trigger conversion: Submit the malicious MVG file to an ImageMagick instance (version < 7.1.2-12) for conversion to SVG, e.g., via magick mvg:malicious.mvg output.svg or through a web application that invokes ImageMagick for image processing.
3. Trigger integer overflow: During WriteSVGImage processing, the number_attributes counter (stored as int) overflows when 6 * BezierQuantum * number_attributes is computed, producing an incorrect (negative or small) value.
4. Trigger buffer overflow: The corrupted number_points value causes ResizeQuantumMemory to allocate an undersized buffer for primitive_info, and subsequent writes to this buffer result in a heap buffer overflow or null pointer dereference.
5. Achieve DoS: The ImageMagick process crashes, causing a Denial of Service for any service relying on it for image processing (GitHub Advisory).

• Process: ImageMagick (magick) process crashing or terminating unexpectedly, particularly during MVG-to-SVG conversion operations.
• Logs: Application or system logs showing segmentation faults, MemoryAllocationFailed errors, or ResourceLimitError exceptions originating from coders/svg.c in ImageMagick.
• File System: Presence of unexpected or malformed .mvg files in directories used for image upload or processing.
• Network: Repeated submission of MVG files to image processing endpoints, especially files with unusually long path token strings.

Upgrade ImageMagick to version 7.1.2-12 or later, which fixes the issue by changing number_attributes from int to size_t and adding explicit overflow checks before arithmetic operations in WriteSVGImage (Fix Commit). Linux distribution patches are available for Debian (DLA-4429-1), Ubuntu (USN-8007-1), Amazon Linux 2 (ALAS2-2026-3123), and openSUSE. As a workaround where immediate patching is not possible, restrict or disable SVG/MVG file processing from untrusted sources, and implement input validation to limit file types accepted by image processing pipelines (Debian LTS, Ubuntu Advisory).

The vulnerability received routine coverage from Linux security news outlets and distribution maintainers, with Debian, Ubuntu, Amazon Linux, and openSUSE all issuing security updates. Tenable published multiple Nessus detection plugins (e.g., plugin IDs 282500, 294893, 297947) for the vulnerability. No notable researcher commentary or significant social media discussion beyond automated CVE tracking posts was identified (Debian LTS, Ubuntu Advisory).