CVE-2023-47994
📋 TL;DR
An integer overflow vulnerability in FreeImage's BMP plugin allows attackers to read memory contents, crash applications, or execute arbitrary code when processing specially crafted BMP images. This affects any application using FreeImage 3.18.0 to parse BMP files. Attackers can exploit this by tricking users into opening malicious images.
💻 Affected Systems
- FreeImage
📦 What is this software?
Freeimage by Freeimage Project
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with the privileges of the application using FreeImage, potentially leading to complete system compromise.
Likely Case
Denial of service (application crash) or information disclosure (memory leak) from malformed BMP files.
If Mitigated
Limited impact if application runs with minimal privileges, uses sandboxing, or validates image sources.
🎯 Exploit Status
Proof-of-concept code is publicly available. Exploitation requires the target to process a malicious BMP file, which can be delivered via email, web uploads, or other file transfer methods.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.19.0 or later
Vendor Advisory: https://freeimage.sourceforge.io/
Restart Required: Yes
Instructions:
1. Download FreeImage 3.19.0 or later from the official repository. 2. Replace the vulnerable FreeImage library files with the patched version. 3. Recompile any applications that statically link FreeImage. 4. Restart affected applications or services.
🔧 Temporary Workarounds
Disable BMP processing
allConfigure applications to reject or skip BMP file processing if not required.
Application-specific configuration required
Input validation
allImplement server-side validation to reject suspicious BMP files before processing.
Implement file signature validation and size limits
🧯 If You Can't Patch
- Isolate applications using FreeImage in restricted network segments or containers.
- Implement strict access controls and monitor for unexpected crashes or memory usage.
🔍 How to Verify
Check if Vulnerable:
Check if FreeImage version 3.18.0 is installed or linked by applications. Use dependency checkers or examine application binaries.Check Version:
On Linux: ldd /path/to/application | grep -i freeimage; On Windows: check DLL versions or use dependency walker tools.Verify Fix Applied:
Verify FreeImage version is 3.19.0 or later. Test with known malicious BMP files to ensure no crashes or memory issues.📡 Detection & Monitoring
Log Indicators:
- Application crashes when processing BMP files
- Unexpected memory access errors in logs
Network Indicators:
- Unusual inbound transfers of BMP files to servers
- Spikes in file uploads to image processing endpoints
SIEM Query:
Example: search for 'segmentation fault' OR 'access violation' in application logs where process name contains 'freeimage' OR file extension is '.bmp'