CVE-2021-31435
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code on Foxit Studio Photo installations by tricking users into opening malicious CMP files. The flaw exists in improper memory initialization during CMP file parsing, enabling code execution in the current process context. Affected users are those running vulnerable versions of Foxit Studio Photo.
💻 Affected Systems
- Foxit Studio Photo
📦 What is this software?
Foxit Studio Photo by Foxitsoftware
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through remote code execution, potentially leading to data theft, ransomware deployment, or lateral movement within the network.
Likely Case
Malware installation or data exfiltration when users open malicious CMP files from untrusted sources.
If Mitigated
Limited impact with proper application sandboxing and user education about opening untrusted files.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious file) but is otherwise straightforward once the vulnerability is understood.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.6.6.932 or later
Vendor Advisory: https://www.foxitsoftware.com/support/security-bulletins.html
Restart Required: Yes
Instructions:
1. Download latest version from Foxit website. 2. Run installer. 3. Restart system. 4. Verify version is 3.6.6.932 or higher.
🔧 Temporary Workarounds
Disable CMP file association
windowsRemove CMP file type association with Foxit Studio Photo to prevent automatic opening
Control Panel > Default Programs > Associate a file type or protocol with a program > Select .cmp > Change program > Choose different application
Application sandboxing
windowsRun Foxit Studio Photo in restricted environment using application control solutions
🧯 If You Can't Patch
- Implement application whitelisting to prevent unauthorized executables
- Deploy email/web filtering to block malicious CMP file delivery
🔍 How to Verify
Check if Vulnerable:
Check Help > About in Foxit Studio Photo for version numberCheck Version:
wmic product where name="Foxit Studio Photo" get versionVerify Fix Applied:
Confirm version is 3.6.6.932 or higher in Help > About📡 Detection & Monitoring
Log Indicators:
- Process creation events for FoxitStudioPhoto.exe with suspicious parent processes
- File access events for .cmp files from unusual locations
Network Indicators:
- Downloads of .cmp files from untrusted sources
- Outbound connections from FoxitStudioPhoto.exe to suspicious IPs
SIEM Query:
process_name="FoxitStudioPhoto.exe" AND file_extension=".cmp" AND source_ip NOT IN (trusted_networks)