CVE-2020-24889
📋 TL;DR
A buffer overflow vulnerability in LibRaw's GetNormalizedModel function allows attackers to execute arbitrary code by providing specially crafted image files. This affects any application using LibRaw library versions before 20.0 to process image files. Users of photo editing software, digital asset management systems, or web applications that process RAW camera images are potentially vulnerable.
💻 Affected Systems
- LibRaw library
- Applications using LibRaw (e.g., darktable, RawTherapee, GIMP with LibRaw plugin, various photo management software)
📦 What is this software?
Libraw by Libraw
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with the privileges of the application using LibRaw, potentially leading to complete system compromise, data theft, or ransomware deployment.
Likely Case
Application crash (denial of service) when processing malicious image files, with potential for limited code execution depending on memory protections.
If Mitigated
Application crash without code execution if modern OS protections (ASLR, DEP) are effective, but still causing service disruption.
🎯 Exploit Status
Proof of concept exists in GitHub issue #334. Exploitation requires crafting a malicious RAW image file and getting the target to process it. Modern exploit mitigations may reduce reliability.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: LibRaw 20.0 and later
Vendor Advisory: https://github.com/LibRaw/LibRaw/issues/334
Restart Required: Yes
Instructions:
1. Update LibRaw to version 20.0 or later. 2. For Linux distributions: Use package manager (apt-get update && apt-get upgrade libraw, yum update libraw, etc.). 3. For Windows/macOS: Download updated version from libraw.org. 4. Rebuild/reinstall any applications that link against LibRaw. 5. Restart affected services or applications.
🔧 Temporary Workarounds
Disable RAW image processing
allTemporarily disable processing of RAW image formats in applications using LibRaw
Application-specific configuration required
Use file type restrictions
allImplement file upload restrictions to block RAW image formats
Web server configuration (e.g., .htaccess, nginx rules) or application-level validation
🧯 If You Can't Patch
- Implement strict input validation for image uploads - reject suspicious or malformed files
- Run applications with minimal privileges and in sandboxed/containerized environments
🔍 How to Verify
Check if Vulnerable:
Check LibRaw version: On Linux: dpkg -l | grep libraw or rpm -qa | grep libraw. For applications: ldd /path/to/application | grep libraw to see linked version.Check Version:
libraw-config --version or check package manager outputVerify Fix Applied:
Confirm LibRaw version is >= 20.0 using version check command. Test processing known safe RAW images to ensure functionality.📡 Detection & Monitoring
Log Indicators:
- Application crashes when processing image files
- Segmentation faults in processes using LibRaw
- Unexpected process termination
Network Indicators:
- Uploads of RAW image files to web applications
- Unusual file transfer patterns
SIEM Query:
Process: (name contains "darktable" OR "rawtherapee" OR "gimp") AND Event: (contains "segmentation fault" OR "SIGSEGV")