CVE-2021-31433
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code by tricking users into opening malicious ARW image files in Foxit Studio Photo. It affects users of Foxit Studio Photo 3.6.6.931 who process untrusted ARW files. The flaw stems from improper validation during ARW file parsing, leading to memory corruption.
💻 Affected Systems
- Foxit Studio Photo
📦 What is this software?
Foxit Studio Photo by Foxitsoftware
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining the same privileges as the current user, potentially leading to data theft, ransomware deployment, or lateral movement.
Likely Case
Local privilege escalation or malware installation on the affected workstation, with potential data exfiltration from the compromised system.
If Mitigated
Limited impact with proper application sandboxing and user privilege restrictions, potentially resulting in application crash only.
🎯 Exploit Status
Exploitation requires user interaction but has low complexity once malicious file is opened. ZDI advisory suggests weaponization is likely.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Update to latest version (check vendor advisory)
Vendor Advisory: https://www.foxitsoftware.com/support/security-bulletins.html
Restart Required: Yes
Instructions:
1. Visit Foxit security bulletins page. 2. Download latest version of Foxit Studio Photo. 3. Install update. 4. Restart system.
🔧 Temporary Workarounds
Disable ARW file association
windowsRemove Foxit Studio Photo as default handler for ARW files to prevent automatic exploitation
Control Panel > Default Programs > Set Associations > Find .ARW > Change to different application
User education and file filtering
allTrain users to avoid opening ARW files from untrusted sources and implement email/web filtering for ARW files
🧯 If You Can't Patch
- Run application with restricted user privileges (non-admin account)
- Implement application whitelisting to prevent unauthorized execution
🔍 How to Verify
Check if Vulnerable:
Check Help > About in Foxit Studio Photo for version 3.6.6.931Check Version:
Not applicable - check via application GUIVerify Fix Applied:
Verify version is updated beyond 3.6.6.931 in Help > About📡 Detection & Monitoring
Log Indicators:
- Application crashes when opening ARW files
- Unexpected process creation from Foxit Studio Photo
Network Indicators:
- Downloads of ARW files from untrusted sources
- Outbound connections after ARW file processing
SIEM Query:
Process Creation where Image contains 'FoxitStudioPhoto.exe' AND Parent Process contains 'explorer.exe'