CVE-2025-66493
📋 TL;DR
A use-after-free vulnerability in Foxit PDF software allows remote code execution when opening malicious PDF files containing crafted JavaScript. This affects Foxit PDF Reader and Foxit PDF Editor users on Windows systems. Attackers can exploit this to take control of affected systems.
💻 Affected Systems
- Foxit PDF Reader
- Foxit PDF Editor
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote attacker gains full system control through arbitrary code execution, potentially leading to data theft, ransomware deployment, or persistent backdoor installation.
Likely Case
Targeted attacks delivering malware or ransomware through malicious PDF attachments in phishing campaigns, compromising individual workstations.
If Mitigated
Limited impact with proper endpoint protection, application sandboxing, and user awareness preventing malicious PDF execution.
🎯 Exploit Status
Exploitation requires user interaction to open malicious PDF. JavaScript execution in PDFs provides attack vector.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2025.2.1, 14.0.1, or 13.2.1 depending on product line
Vendor Advisory: https://www.foxit.com/support/security-bulletins.html
Restart Required: Yes
Instructions:
1. Open Foxit software. 2. Go to Help > Check for Updates. 3. Follow prompts to install latest version. 4. Restart computer after installation.
🔧 Temporary Workarounds
Disable JavaScript in Foxit
windowsPrevents JavaScript execution in PDF files, blocking the exploitation vector.
Open Foxit > File > Preferences > JavaScript > Uncheck 'Enable JavaScript'
Use Protected View
windowsOpen PDFs in restricted mode that prevents script execution.
Open Foxit > File > Preferences > Trust Manager > Check 'Enable Safe Reading Mode'
🧯 If You Can't Patch
- Block PDF files at email gateways and web proxies
- Implement application whitelisting to prevent unauthorized PDF execution
🔍 How to Verify
Check if Vulnerable:
Check Foxit version in Help > About. If version is below 2025.2.1, 14.0.1, or 13.2.1, system is vulnerable.Check Version:
wmic product where "name like 'Foxit%'" get name, versionVerify Fix Applied:
Confirm version is 2025.2.1, 14.0.1, or 13.2.1 or higher in Help > About.📡 Detection & Monitoring
Log Indicators:
- Foxit process crashes with memory access violations
- Unexpected JavaScript execution in PDF files
- Process spawning from Foxit executables
Network Indicators:
- Downloads of PDF files from suspicious sources
- Outbound connections from Foxit processes
SIEM Query:
process_name:"Foxit*.exe" AND (event_id:1000 OR event_id:1001) OR process_parent_name:"Foxit*.exe"