CVE-2021-30356
📋 TL;DR
A privilege escalation vulnerability in Check Point Identity Agent allows low-privileged users to overwrite protected system files, potentially leading to denial of service or system compromise. This affects all systems running Check Point Identity Agent versions before R81.018.0000. The vulnerability requires local access to the system.
💻 Affected Systems
- Check Point Identity Agent
📦 What is this software?
Identity Agent by Checkpoint
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through privilege escalation, allowing attackers to execute arbitrary code with SYSTEM/root privileges, install persistent backdoors, or render the system inoperable.
Likely Case
Denial of service through critical system file corruption, potentially disrupting authentication services and requiring system restoration from backups.
If Mitigated
Limited impact if proper file permissions and user privilege separation are enforced, though the vulnerability still presents a security risk.
🎯 Exploit Status
Exploitation requires local user access but is relatively straightforward once access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: R81.018.0000 or later
Vendor Advisory: https://supportcontent.checkpoint.com/solutions?id=sk134312
Restart Required: Yes
Instructions:
1. Download Identity Agent version R81.018.0000 or later from Check Point support portal. 2. Run the installer with administrative privileges. 3. Restart the system after installation completes.
🔧 Temporary Workarounds
Restrict local user access
allLimit local user accounts to only essential personnel and implement strict access controls.
Implement file integrity monitoring
allMonitor critical system files for unauthorized modifications using tools like Tripwire or Windows File Integrity Monitoring.
🧯 If You Can't Patch
- Isolate affected systems from critical network segments
- Implement strict user privilege management and monitor for suspicious file modification activities
🔍 How to Verify
Check if Vulnerable:
Check Identity Agent version via Control Panel (Windows) or package manager (Linux). If version is below R81.018.0000, system is vulnerable.Check Version:
Windows: Check 'Programs and Features' in Control Panel. Linux: rpm -qa | grep -i identity-agent or dpkg -l | grep -i identity-agentVerify Fix Applied:
Verify Identity Agent version is R81.018.0000 or higher after patching.📡 Detection & Monitoring
Log Indicators:
- Unexpected file modification events in system logs
- Identity Agent service crashes or abnormal behavior
- Failed authentication attempts followed by file access anomalies
Network Indicators:
- Unusual outbound connections from Identity Agent processes
- Authentication service disruptions
SIEM Query:
source="windows-security" EventID=4663 OR source="syslog" message="*Identity Agent*" AND (message="*modif*" OR message="*access denied*")