CVE-2022-28673
📋 TL;DR
This is a use-after-free vulnerability in Foxit PDF Reader that allows remote attackers to execute arbitrary code when a user opens a malicious PDF file or visits a malicious webpage. The vulnerability exists due to improper validation of Doc objects before performing operations. All users running affected versions of Foxit PDF Reader are at risk.
💻 Affected Systems
- Foxit PDF Reader
📦 What is this software?
⚠️ 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 within the network.
Likely Case
Malware installation on the victim's system, credential theft, or system disruption through arbitrary code execution in the context of the PDF reader process.
If Mitigated
Limited impact with proper application sandboxing, restricted user privileges, and network segmentation preventing lateral movement.
🎯 Exploit Status
Exploitation requires user interaction but has been publicly disclosed through ZDI. The vulnerability is a use-after-free (CWE-416) that can lead to arbitrary code execution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 11.2.2 and later
Vendor Advisory: https://www.foxit.com/support/security-bulletins.html
Restart Required: Yes
Instructions:
1. Open Foxit PDF Reader. 2. Go to Help > Check for Updates. 3. Follow prompts to download and install version 11.2.2 or later. 4. Restart the application.
🔧 Temporary Workarounds
Disable JavaScript in Foxit Reader
allPrevents exploitation through malicious JavaScript in PDF files
Open Foxit Reader > File > Preferences > JavaScript > Uncheck 'Enable JavaScript'
Use Protected View
allOpen PDFs in protected mode to limit potential damage
Open Foxit Reader > File > Preferences > Trust Manager > Check 'Enable Safe Reading Mode'
🧯 If You Can't Patch
- Use alternative PDF readers that are not affected by this vulnerability
- Implement application whitelisting to block execution of Foxit Reader
🔍 How to Verify
Check if Vulnerable:
Check Foxit Reader version: Open Foxit Reader > Help > About Foxit Reader. If version is 11.2.1.53537 or earlier, you are vulnerable.Check Version:
On Windows: wmic product where name='Foxit Reader' get versionVerify Fix Applied:
Verify version is 11.2.2 or later in Help > About Foxit Reader. Test opening known safe PDF files to ensure functionality.📡 Detection & Monitoring
Log Indicators:
- Unexpected Foxit Reader crashes
- Multiple PDF file openings from untrusted sources
- Process creation from Foxit Reader with unusual command lines
Network Indicators:
- Downloads of PDF files from suspicious domains
- Outbound connections from Foxit Reader process to unknown IPs
SIEM Query:
process_name='FoxitReader.exe' AND (event_id=1000 OR event_id=1001) AND command_line CONTAINS '.pdf'