CVE-2018-25012
📋 TL;DR
A heap-based buffer overflow vulnerability in libwebp's GetLE24() function allows attackers to execute arbitrary code or cause denial of service by processing malicious WebP images. This affects any application using vulnerable versions of libwebp for image processing, including web browsers, image viewers, and server-side applications.
💻 Affected Systems
- libwebp
- Google Chrome
- Mozilla Firefox
- Chromium-based browsers
- ImageMagick
- GIMP
- other software using libwebp
📦 What is this software?
Libwebp by Webmproject
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, or ransomware deployment.
Likely Case
Application crashes (denial of service) when processing malicious WebP images, potentially disrupting services.
If Mitigated
Limited impact with proper sandboxing and memory protection mechanisms in place.
🎯 Exploit Status
Proof-of-concept available in Chromium bug reports. Exploitation requires processing a malicious WebP image.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: libwebp 1.0.1 and later
Vendor Advisory: https://chromium.googlesource.com/webm/libwebp/+/95fd65070662e01cc9170c4444f5c0859a710097
Restart Required: Yes
Instructions:
1. Update libwebp to version 1.0.1 or later. 2. Update all dependent applications (browsers, image processors). 3. Restart affected services and applications.
🔧 Temporary Workarounds
Disable WebP processing
allTemporarily disable WebP image processing in applications if possible.
Application-specific configuration changes required
Input validation
allImplement strict validation of WebP images before processing.
Implement file signature validation and size limits
🧯 If You Can't Patch
- Implement network segmentation to isolate vulnerable systems
- Deploy application sandboxing and memory protection (ASLR, DEP)
🔍 How to Verify
Check if Vulnerable:
Check libwebp version: `libwebp --version` or `dpkg -l | grep libwebp` or `rpm -qa | grep libwebp`Check Version:
libwebp --version 2>/dev/null || dpkg -l libwebp* 2>/dev/null || rpm -q libwebp 2>/dev/nullVerify Fix Applied:
Confirm libwebp version is 1.0.1 or later and test with known malicious WebP samples.📡 Detection & Monitoring
Log Indicators:
- Application crashes with segmentation faults
- Memory access violation errors
- Unexpected process termination
Network Indicators:
- Unusual outbound connections after image processing
- Large volume of WebP image uploads
SIEM Query:
source="application_logs" AND ("segmentation fault" OR "buffer overflow" OR "SIGSEGV") AND process="*webp*"🔗 References
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=9123
- https://bugzilla.redhat.com/show_bug.cgi?id=1956922
- https://chromium.googlesource.com/webm/libwebp/+/95fd65070662e01cc9170c4444f5c0859a710097
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=9123
- https://bugzilla.redhat.com/show_bug.cgi?id=1956922
- https://chromium.googlesource.com/webm/libwebp/+/95fd65070662e01cc9170c4444f5c0859a710097
