CVE-2024-9255
📋 TL;DR
This is a use-after-free vulnerability in Foxit PDF Reader's annotation handling that allows remote attackers to execute arbitrary code when users open malicious PDF files. Attackers can exploit this to gain control of affected systems running vulnerable versions. All users of Foxit PDF Reader with affected versions are at risk.
💻 Affected Systems
- Foxit PDF Reader
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining full control of the victim's computer, potentially leading to data theft, ransomware deployment, or lateral movement within the network.
Likely Case
Local privilege escalation leading to malware installation, credential theft, or persistence mechanisms being established on the compromised system.
If Mitigated
Application crash or denial of service if exploit attempts are blocked by security controls, with no code execution achieved.
🎯 Exploit Status
Exploitation requires user interaction (opening a malicious PDF) but the vulnerability is in a commonly used component. ZDI has confirmed the vulnerability and exploitation is likely given the impact.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2024.3 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 2024.3 or later. 4. Restart the application after installation completes.
🔧 Temporary Workarounds
Disable JavaScript in Foxit Reader
allPrevents JavaScript-based exploitation vectors that might be used to trigger the vulnerability
File > Preferences > JavaScript > Uncheck 'Enable JavaScript'
Use Protected View
windowsOpen PDFs in protected/sandboxed mode to limit potential damage
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
- Block PDF files from untrusted sources at network perimeter or email gateway
🔍 How to Verify
Check if Vulnerable:
Check Foxit Reader version: Open Foxit Reader, go to Help > About Foxit Reader. If version is below 2024.3, the system is vulnerable.Check Version:
On Windows: wmic product where name="Foxit Reader" get versionVerify Fix Applied:
After updating, verify version is 2024.3 or higher in Help > About Foxit Reader. Test with known safe PDF files to ensure functionality.📡 Detection & Monitoring
Log Indicators:
- Application crashes of Foxit Reader with memory access violations
- Unusual child processes spawned from Foxit Reader
- Multiple failed annotation operations in application logs
Network Indicators:
- Downloads of PDF files from suspicious sources followed by Foxit Reader execution
- Outbound connections from Foxit Reader process to unknown IPs
SIEM Query:
process_name:"FoxitReader.exe" AND (event_id:1000 OR event_id:1001) AND faulting_module:"FoxitReader.exe"