CVE-2023-7317
📋 TL;DR
Nagios XI versions before 2024R1 have a missing access control vulnerability in the Web SSH Terminal. Remote attackers with low privileges can access the terminal without proper authorization, potentially executing unauthorized commands or accessing sensitive information. Organizations running vulnerable Nagios XI versions are affected.
💻 Affected Systems
- Nagios XI
📦 What is this software?
Nagios Xi by Nagios
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise via unauthorized command execution, data exfiltration, lateral movement within the network, and persistence establishment.
Likely Case
Unauthorized access to sensitive system information, limited command execution within user context, potential privilege escalation.
If Mitigated
Limited impact due to network segmentation, strong authentication controls, and monitoring preventing successful exploitation.
🎯 Exploit Status
Requires low-privileged authenticated access to Nagios XI interface.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2024R1 and later
Vendor Advisory: https://www.nagios.com/changelog/nagios-xi/
Restart Required: Yes
Instructions:
1. Backup current Nagios XI configuration. 2. Download Nagios XI 2024R1 or later from official portal. 3. Follow Nagios XI upgrade documentation. 4. Restart Nagios XI services. 5. Verify Web SSH Terminal access controls.
🔧 Temporary Workarounds
Disable Web SSH Terminal
allTemporarily disable the vulnerable Web SSH Terminal feature
Navigate to Admin > System Extensions > Manage Components > Disable 'Web SSH Terminal'
Restrict Network Access
linuxLimit access to Nagios XI interface using firewall rules
iptables -A INPUT -p tcp --dport 80 -s trusted_networks -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s trusted_networks -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Implement strict network segmentation to isolate Nagios XI from critical systems
- Enable detailed logging and monitoring for Web SSH Terminal access attempts
🔍 How to Verify
Check if Vulnerable:
Check Nagios XI version in Admin > System Extensions > About Nagios XI. If version is below 2024R1, system is vulnerable.Check Version:
grep 'nagios_version' /usr/local/nagiosxi/var/xiversionVerify Fix Applied:
After upgrade, verify version is 2024R1 or later. Test Web SSH Terminal access with low-privileged user - should be denied.📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to /nagiosxi/admin/ssh_terminal.php
- SSH terminal sessions from unexpected user accounts
- Failed authorization checks in Nagios XI logs
Network Indicators:
- Unusual SSH traffic patterns from Nagios XI server
- Unexpected outbound connections from Nagios XI server
SIEM Query:
source="nagiosxi" AND (uri="/admin/ssh_terminal.php" OR event="SSH Terminal Access") AND user!="admin"