CVE-2021-34280
📋 TL;DR
CVE-2021-34280 is an uninitialized pointer vulnerability in Polaris Office that allows remote code execution when a user opens a malicious PDF file. This affects Polaris Office v9.103.83.44230 users who process PDF documents. Attackers can exploit this to execute arbitrary code with the privileges of the user running Polaris Office.
💻 Affected Systems
- Polaris Office
📦 What is this software?
Polaris Office by Polarisoffice
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining the same privileges as the user, potentially leading to data theft, ransomware deployment, or lateral movement within the network.
Likely Case
Local privilege escalation leading to malware installation, data exfiltration, or persistence mechanisms being established on the affected system.
If Mitigated
Limited impact with proper application sandboxing and user privilege restrictions, potentially only causing application crashes.
🎯 Exploit Status
Exploitation requires user interaction to open a crafted PDF file. Public proof-of-concept code exists in GitHub repositories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after v9.103.83.44230
Vendor Advisory: https://www.polarisoffice.com/security
Restart Required: Yes
Instructions:
1. Open Polaris Office. 2. Go to Help > Check for Updates. 3. Install available updates. 4. Restart Polaris Office. 5. Verify version is newer than v9.103.83.44230.
🔧 Temporary Workarounds
Disable PDF handling in Polaris Office
allConfigure Polaris Office to use external PDF viewer instead of built-in engine
Open Polaris Office > Settings > File Association > Uncheck PDF
Application sandboxing
windowsRun Polaris Office with reduced privileges using application control solutions
🧯 If You Can't Patch
- Block PDF file extensions at email gateways and web proxies
- Implement application whitelisting to prevent unauthorized code execution
🔍 How to Verify
Check if Vulnerable:
Check Polaris Office version in Help > About. If version is exactly v9.103.83.44230, system is vulnerable.Check Version:
On Windows: wmic product where name="Polaris Office" get versionVerify Fix Applied:
Verify Polaris Office version is newer than v9.103.83.44230 after updating.📡 Detection & Monitoring
Log Indicators:
- PolarisOffice.exe crashes with access violation errors
- Unusual child processes spawned from PolarisOffice.exe
Network Indicators:
- Outbound connections from Polaris Office to unusual destinations
- DNS requests for command and control domains
SIEM Query:
Process Creation where Image contains "PolarisOffice.exe" and CommandLine contains ".pdf"