CVE-2023-6926
📋 TL;DR
This vulnerability allows authenticated SSH users with limited access on Crestron AM-300 devices to execute arbitrary OS commands and escalate privileges to root. It affects organizations using Crestron AM-300 conference room automation systems with vulnerable firmware.
💻 Affected Systems
- Crestron AM-300
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with root access, enabling attacker to install persistent backdoors, exfiltrate sensitive data, or pivot to other network systems.
Likely Case
Privilege escalation from limited SSH user to root, allowing complete control of the AM-300 device and potential access to connected conference room systems.
If Mitigated
Limited impact if SSH access is restricted to trusted users only and proper network segmentation is in place.
🎯 Exploit Status
Exploitation requires authenticated SSH access. Command injection vulnerabilities are typically easy to weaponize once details are known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Crestron advisory for latest patched version
Vendor Advisory: https://www.crestron.com/Security/Security_Advisories
Restart Required: Yes
Instructions:
1. Check current firmware version. 2. Download latest firmware from Crestron portal. 3. Upload and install via web interface. 4. Reboot device. 5. Verify update completed successfully.
🔧 Temporary Workarounds
Disable SSH Access
linuxTemporarily disable SSH service if not required for operations
systemctl stop sshd
systemctl disable sshd
Restrict SSH Access
linuxLimit SSH access to specific IP addresses using firewall rules
iptables -A INPUT -p tcp --dport 22 -s [TRUSTED_IP] -j ACCEPT
iptables -A INPUT -p tcp --dport 22 -j DROP
🧯 If You Can't Patch
- Implement strict network segmentation to isolate AM-300 devices from critical systems
- Monitor SSH logs for suspicious activity and implement alerting for privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check firmware version via web interface or SSH: cat /etc/versionCheck Version:
cat /etc/version || grep -i version /proc/cmdlineVerify Fix Applied:
Verify firmware version is updated beyond 1.4499.00018 and test SSH command injection attempts fail📡 Detection & Monitoring
Log Indicators:
- Unusual SSH login patterns
- Commands with shell metacharacters in SSH logs
- Sudden privilege escalation attempts
Network Indicators:
- Unexpected outbound connections from AM-300
- SSH traffic from unusual sources
SIEM Query:
source="ssh_logs" AND (command="*;*" OR command="*|*" OR command="*`*" OR command="*$(*")