CVE-2024-9114
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code by tricking users into opening malicious GIF files in FastStone Image Viewer. The flaw exists in GIF parsing where improper validation leads to buffer overflow. All users of affected FastStone Image Viewer versions are at risk.
💻 Affected Systems
- FastStone Image Viewer
📦 What is this software?
Image Viewer by Faststone
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining full control of the victim's computer, potentially leading to data theft, ransomware deployment, or lateral movement within the network.
Likely Case
Attacker gains code execution with user privileges, enabling data exfiltration, credential theft, and installation of additional malware.
If Mitigated
Limited impact with proper application sandboxing and user privilege restrictions, potentially containing damage to user profile only.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious file) but the technical exploit complexity is low once the malicious file is accessed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 7.7 or later
Vendor Advisory: https://www.faststone.org/FSViewerDetail.htm
Restart Required: No
Instructions:
1. Download latest version from FastStone website
2. Run installer
3. Follow installation prompts
4. Verify version is 7.7 or higher
🔧 Temporary Workarounds
Disable GIF file association
windowsPrevent FastStone Image Viewer from automatically opening GIF files
Control Panel > Default Programs > Set Default Programs > Select FastStone Image Viewer > Choose defaults for this program > Uncheck .gif
Use alternative image viewer
windowsTemporarily use a different application for viewing GIF files
🧯 If You Can't Patch
- Restrict user permissions to prevent execution of arbitrary code
- Implement application whitelisting to block unauthorized executables
🔍 How to Verify
Check if Vulnerable:
Check FastStone Image Viewer version in Help > AboutCheck Version:
Not applicable - check via GUI Help > About menuVerify Fix Applied:
Confirm version is 7.7 or higher in Help > About📡 Detection & Monitoring
Log Indicators:
- Unexpected FastStone Image Viewer crashes
- Process creation from FastStone Image Viewer with unusual parameters
Network Indicators:
- Outbound connections from FastStone Image Viewer process to unknown IPs
SIEM Query:
Process:FastStone Image Viewer AND (EventID:1000 OR ParentImage:*malicious*)