CVE-2020-8848
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code by tricking users into opening malicious JPG2000 image files in Foxit Reader. Attackers can exploit improper memory validation to write beyond allocated structures and gain code execution in the current process context. All users running vulnerable versions of Foxit Reader are affected.
💻 Affected Systems
- Foxit Reader
📦 What is this software?
Phantompdf by Foxitsoftware
Reader by Foxitsoftware
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through remote code execution, allowing attackers to install malware, steal data, or pivot to other systems.
Likely Case
Malware installation through phishing campaigns using malicious JPG2000 files, leading to data theft or ransomware deployment.
If Mitigated
Limited impact with proper patching and user awareness training preventing successful exploitation.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious file) but the technical complexity is low once the malicious file is opened. Proof-of-concept code has been published.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 9.7.1.29511 and later
Vendor Advisory: https://www.foxitsoftware.com/support/security-bulletins.php
Restart Required: No
Instructions:
1. Open Foxit Reader. 2. Go to Help > Check for Updates. 3. Follow prompts to update to version 9.7.1.29511 or later. 4. Alternatively, download latest version from Foxit website and install.
🔧 Temporary Workarounds
Disable JPG2000 file association
windowsRemove Foxit Reader as default handler for JPG2000 files to prevent automatic opening
Windows: Control Panel > Default Programs > Set Default Programs > Select Foxit Reader > Choose defaults > Uncheck .jp2, .j2k, .jpc, .jpx extensions
Use alternative PDF reader
allTemporarily use a different PDF reader that doesn't have this vulnerability
🧯 If You Can't Patch
- Implement application whitelisting to prevent execution of unauthorized code
- Deploy network filtering to block JPG2000 files from untrusted sources and educate users about file attachment risks
🔍 How to Verify
Check if Vulnerable:
Open Foxit Reader, go to Help > About Foxit Reader, check if version is 9.7.0.29455 or earlierCheck Version:
Windows: "C:\Program Files (x86)\Foxit Software\Foxit Reader\FoxitReader.exe" --versionVerify Fix Applied:
Verify version is 9.7.1.29511 or later in Help > About Foxit Reader📡 Detection & Monitoring
Log Indicators:
- Application crashes in Foxit Reader with JPG2000 files
- Unexpected process creation from Foxit Reader
Network Indicators:
- Downloads of JPG2000 files from suspicious sources
- Outbound connections from Foxit Reader to unknown IPs
SIEM Query:
process_name:"FoxitReader.exe" AND (event_id:1000 OR event_id:1001) AND file_extension:(".jp2" OR ".j2k" OR ".jpc" OR ".jpx")