CVE-2021-31468
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code by exploiting a memory corruption flaw in Foxit Reader's U3D file handling. Attackers can achieve code execution in the current process context by tricking users into opening malicious PDF files containing specially crafted U3D objects. Users of Foxit Reader 10.1.3.37598 are affected.
💻 Affected Systems
- Foxit Reader
📦 What is this software?
3d by Foxitsoftware
3d by Foxitsoftware
3d by Foxitsoftware
3d by Foxitsoftware
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through arbitrary code execution with the privileges of the Foxit Reader process, potentially leading to data theft, ransomware deployment, or lateral movement within the network.
Likely Case
Malware installation or data exfiltration from the compromised system, as attackers typically use such vulnerabilities to establish footholds for further attacks.
If Mitigated
Limited impact if proper application sandboxing, least privilege principles, and network segmentation are implemented, potentially containing the exploit to the application sandbox.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious PDF) but is straightforward once the malicious file is executed. ZDI published details and proof-of-concept.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 10.1.4 or later
Vendor Advisory: https://www.foxitsoftware.com/support/security-bulletins.php
Restart Required: Yes
Instructions:
1. Download latest Foxit Reader from official website. 2. Run installer. 3. Restart system. 4. Verify version is 10.1.4 or higher.
🔧 Temporary Workarounds
Disable U3D support
allPrevent Foxit Reader from processing U3D content by disabling the feature
Navigate to Edit > Preferences > 3D & Multimedia > Uncheck 'Enable U3D support'
Use alternative PDF reader
allTemporarily switch to a different PDF reader that isn't affected
🧯 If You Can't Patch
- Implement application whitelisting to block unauthorized executables
- Deploy network segmentation to limit lateral movement from compromised systems
🔍 How to Verify
Check if Vulnerable:
Check Foxit Reader version in Help > About. If version is 10.1.3.37598 or earlier, system is vulnerable.Check Version:
On Windows: wmic product where name="Foxit Reader" get versionVerify Fix Applied:
Verify version is 10.1.4 or later in Help > About. Test with known safe PDF containing U3D content.📡 Detection & Monitoring
Log Indicators:
- Foxit Reader crash logs with memory access violations
- Unexpected process creation from Foxit Reader
Network Indicators:
- Outbound connections from Foxit Reader to unknown IPs
- DNS requests for suspicious domains after PDF opening
SIEM Query:
process_name:"FoxitReader.exe" AND (event_id:1000 OR event_id:1001) OR process_parent_name:"FoxitReader.exe" AND process_name NOT IN (allowed_list)