CVE-2020-22650
📋 TL;DR
A memory leak vulnerability in AlienVault OSSIM v5's sim-organizer.c component causes system crashes when processing large numbers of alarm events, leading to denial of service. This affects organizations using AlienVault OSSIM v5 for security monitoring and incident response.
💻 Affected Systems
- AlienVault OSSIM
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system crash and unavailability of the OSSIM platform, disrupting security monitoring and incident response capabilities.
Likely Case
System instability and periodic crashes under high alarm load, requiring manual restarts and causing monitoring gaps.
If Mitigated
Reduced performance during peak alarm periods but no complete system failure if resource limits are enforced.
🎯 Exploit Status
Exploitation requires ability to generate alarm events, which typically requires some level of access to the OSSIM system or monitored infrastructure.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 5.8.2 and later
Vendor Advisory: https://github.com/jpalanco/alienvault-ossim/issues/4
Restart Required: Yes
Instructions:
1. Backup current OSSIM configuration. 2. Update to OSSIM v5.8.2 or later via the official update mechanism. 3. Restart the OSSIM services. 4. Verify the update was successful.
🔧 Temporary Workarounds
Limit Alarm Generation Rate
linuxConfigure alarm generation thresholds to prevent the large volume of events that triggers the memory leak.
# Configure in OSSIM web interface: Administration → Configuration → Alarm Management
Resource Monitoring and Restart Script
linuxMonitor memory usage of sim-organizer process and restart if memory consumption exceeds safe thresholds.
#!/bin/bash
while true; do
mem_usage=$(ps aux | grep sim-organizer | grep -v grep | awk '{print $4}')
if [ $(echo "$mem_usage > 80" | bc) -eq 1 ]; then
systemctl restart ossim-server
fi
sleep 300
done
🧯 If You Can't Patch
- Implement strict rate limiting on alarm generation sources
- Deploy redundant OSSIM instances with load balancing to maintain availability during potential crashes
🔍 How to Verify
Check if Vulnerable:
Check OSSIM version: cat /etc/ossim/ossim_setup.conf | grep versionCheck Version:
cat /etc/ossim/ossim_setup.conf | grep versionVerify Fix Applied:
Verify version is 5.8.2 or higher and monitor sim-organizer process memory usage during high alarm periods.📡 Detection & Monitoring
Log Indicators:
- Repeated sim-organizer process crashes in /var/log/ossim/server.log
- Memory allocation failures in system logs
- Sudden service restarts
Network Indicators:
- Unusual spike in alarm-related network traffic to OSSIM server
- Loss of monitoring connectivity
SIEM Query:
source="/var/log/ossim/server.log" AND "sim-organizer" AND ("crash" OR "segmentation fault" OR "out of memory")