CVE-2023-27339
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code by tricking users into opening malicious PNG files in PDF-XChange Editor. The flaw exists in PNG parsing where crafted data triggers an out-of-bounds write. All users of affected PDF-XChange Editor versions are at risk.
💻 Affected Systems
- PDF-XChange Editor
📦 What is this software?
Pdf Tools by Pdf Xchange
Pdf Xchange Editor by Pdf Xchange
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining full control of the affected system, potentially leading to data theft, ransomware deployment, or lateral movement.
Likely Case
Remote code execution in the context of the current user, allowing file system access, credential theft, and installation of malware.
If Mitigated
Limited impact with proper application sandboxing and user privilege restrictions, potentially containing the exploit to the application context.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious file) but the technical complexity is low once the file is opened.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 9.5.368.0 and later
Vendor Advisory: https://www.tracker-software.com/product/pdf-xchange-editor/history
Restart Required: Yes
Instructions:
1. Open PDF-XChange Editor
2. Go to Help > Check for Updates
3. Follow prompts to download and install version 9.5.368.0 or later
4. Restart the application
🔧 Temporary Workarounds
Disable PNG file processing
windowsBlock PNG files from being processed by PDF-XChange Editor via file association changes
Windows Registry: Modify HKEY_CLASSES_ROOT\.png to remove PDF-XChange Editor associations
Application sandboxing
windowsRun PDF-XChange Editor in restricted mode or sandboxed environment
Use Windows Sandbox or third-party application sandboxing tools
🧯 If You Can't Patch
- Implement application whitelisting to block execution of PDF-XChange Editor
- Use network segmentation to isolate systems running vulnerable versions
🔍 How to Verify
Check if Vulnerable:
Check Help > About in PDF-XChange Editor and verify version is below 9.5.368.0Check Version:
PDFXEdit.exe /version (from command line) or check Help > About in GUIVerify Fix Applied:
Confirm version is 9.5.368.0 or higher in Help > About📡 Detection & Monitoring
Log Indicators:
- Application crashes with PNG file processing
- Unusual process creation from PDF-XChange Editor
- Memory access violation events in Windows Event Logs
Network Indicators:
- Downloads of PNG files followed by PDF-XChange Editor execution
- Unusual outbound connections from PDF-XChange Editor process
SIEM Query:
Process Creation where Image contains 'PDFXEdit.exe' AND Parent Process contains 'explorer.exe' AND Command Line contains '.png'