CVE-2024-31570: FreeImage Buffer Overflow Vulnerability

CVE-2024-31570 Overview

CVE-2024-31570 is a critical stack-based buffer overflow vulnerability affecting libfreeimage in FreeImage versions 3.4.0 through 3.18.0. The vulnerability exists in the PluginXPM.cpp Load function and can be triggered when processing a maliciously crafted XPM (X PixMap) image file. Successful exploitation could allow an attacker to execute arbitrary code or cause a denial of service condition.

Critical Impact

This stack-based buffer overflow vulnerability allows remote attackers to potentially execute arbitrary code by crafting malicious XPM image files processed by vulnerable FreeImage library instances.

Affected Products

• FreeImage 3.4.0 through 3.18.0
• Applications and software utilizing libfreeimage for image processing
• Systems with FreeImage library dependencies for XPM file handling

Discovery Timeline

• 2024-04-11 - Vulnerability disclosed on Openwall OSS Security Mailing List
• 2024-09-19 - CVE CVE-2024-31570 published to NVD
• 2024-09-25 - Last updated in NVD database

Technical Details for CVE-2024-31570

Vulnerability Analysis

This vulnerability is classified as CWE-787 (Out-of-Bounds Write) and CWE-121 (Stack-based Buffer Overflow). The flaw resides in the Load function within PluginXPM.cpp, which handles the parsing and loading of XPM image files. When processing specially crafted XPM files with malformed header information or pixel data, the function fails to properly validate input boundaries before writing data to stack-allocated buffers.

The vulnerability can be exploited remotely over a network without requiring authentication or user interaction, making it particularly dangerous in environments where FreeImage processes untrusted image files automatically.

Root Cause

The root cause of this vulnerability is improper input validation in the XPM file parsing logic. The Load function in PluginXPM.cpp allocates fixed-size buffers on the stack to store image data during parsing operations. When processing XPM files with dimensions or color definitions that exceed expected boundaries, the parser writes beyond the allocated buffer space, corrupting adjacent stack memory. This lack of bounds checking enables attackers to overwrite critical stack data including return addresses and saved registers.

Attack Vector

The attack vector is network-based, requiring an attacker to deliver a malicious XPM file to a system running vulnerable FreeImage software. Attack scenarios include:

1. Uploading malicious XPM files to web applications that use FreeImage for image processing
2. Sending crafted XPM files via email or file sharing platforms to victims using vulnerable image viewers
3. Embedding malicious XPM files in documents or archives processed by applications linked against FreeImage
4. Hosting malicious XPM files on websites visited by users with vulnerable FreeImage-based applications

The vulnerability requires no special privileges and can be triggered without user interaction in automated image processing pipelines. Exploitation could result in complete system compromise with the same privileges as the application processing the malicious file.

For detailed technical information about the vulnerability mechanism, refer to the SourceForge Bug Report and the Openwall OSS Security Mailing List disclosure.

Detection Methods for CVE-2024-31570

Indicators of Compromise

• Presence of malformed XPM files with abnormally large dimension values or excessive color definitions in upload directories or temp folders
• Application crashes or segmentation faults in processes linked against FreeImage when processing XPM files
• Unexpected memory access violations in PluginXPM.cpp related code paths
• Anomalous process behavior following XPM file processing operations

Detection Strategies

• Implement file integrity monitoring for FreeImage library files to detect unauthorized modifications
• Deploy endpoint detection solutions capable of identifying buffer overflow exploitation attempts
• Configure application crash analysis to flag recurring failures in image processing components
• Use static analysis tools to identify vulnerable FreeImage library versions in your software inventory

Monitoring Recommendations

• Enable detailed logging for all image processing operations, particularly XPM file handling
• Monitor for unusual process memory consumption patterns during image file processing
• Implement alerting for application crashes involving FreeImage library components
• Track and audit all XPM file uploads and processing events in web applications

How to Mitigate CVE-2024-31570

Immediate Actions Required

• Identify all systems and applications using FreeImage versions 3.4.0 through 3.18.0
• Restrict or disable XPM file processing in affected applications until patches are applied
• Implement input validation to reject XPM files from untrusted sources
• Consider replacing FreeImage with alternative image processing libraries if patches are unavailable

Patch Information

As of the last NVD update on 2024-09-25, users should monitor the FreeImage SourceForge project for official patch releases. Organizations should review the Openwall OSS Security Mailing List for additional mitigation guidance and updates from the security community.

Workarounds

• Disable XPM format support in FreeImage by removing or renaming the XPM plugin if not required for operations
• Implement strict file type validation to block XPM files at the application boundary
• Run applications using FreeImage in sandboxed environments with reduced privileges
• Deploy network-level filtering to inspect and quarantine XPM files before they reach processing systems

# Example: Disable XPM plugin by removing from FreeImage plugins directory
# Locate FreeImage installation
find /usr -name "FreeImage*" -type f 2>/dev/null

# If using dynamic plugins, remove or rename XPM plugin
# mv /path/to/freeimage/plugins/PluginXPM.so /path/to/freeimage/plugins/PluginXPM.so.disabled

# Restrict file permissions on image processing directories
chmod 750 /path/to/image/processing/directory