CVE-2025-50989
📋 TL;DR
CVE-2025-50989 is an authenticated command injection vulnerability in OPNsense firewall software that allows administrators to execute arbitrary system commands via the Bridge Interface Edit endpoint. Successful exploitation leads to remote code execution with root privileges, potentially resulting in complete system compromise. Only OPNsense installations with administrator accounts are affected.
💻 Affected Systems
- OPNsense
📦 What is this software?
Opnsense by Opnsense
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with root access, lateral movement to other systems, data exfiltration, and persistent backdoor installation.
Likely Case
Unauthorized administrative access leading to configuration changes, service disruption, or credential theft.
If Mitigated
Limited impact due to strong access controls, network segmentation, and monitoring preventing successful exploitation.
🎯 Exploit Status
Exploitation requires administrator credentials but is straightforward once authenticated. Public proof-of-concept demonstrates command injection via the span parameter.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 25.1.8
Vendor Advisory: https://github.com/opnsense/changelog/blob/640e96ed6a783254283aead0d0b744fc9143ce6d/community/25.1/25.1.8#L34
Restart Required: No
Instructions:
1. Log into OPNsense web interface as administrator. 2. Navigate to System > Firmware > Updates. 3. Click 'Check for updates'. 4. Apply available updates to upgrade to version 25.1.8 or later.
🔧 Temporary Workarounds
Restrict Bridge Interface Access
allRemove administrator access to bridge interface configuration for non-essential users.
Network Segmentation
allIsolate OPNsense management interface from untrusted networks.
🧯 If You Can't Patch
- Implement strict access controls to limit which administrators can modify bridge interfaces.
- Deploy network monitoring and intrusion detection to alert on suspicious command execution patterns.
🔍 How to Verify
Check if Vulnerable:
Check OPNsense version via web interface dashboard or CLI. If version is below 25.1.8, system is vulnerable.Check Version:
opnsense-versionVerify Fix Applied:
Confirm version is 25.1.8 or higher via System > Firmware > Status in web interface.📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in system logs
- Multiple failed authentication attempts followed by bridge interface modifications
- Suspicious POST requests to interfaces_bridge_edit.php with shell operators in span parameter
Network Indicators:
- Unexpected outbound connections from OPNsense system
- Anomalous traffic patterns from management interface
SIEM Query:
source="opnsense" AND (uri_path="/interfaces_bridge_edit.php" AND span="*;*" OR span="*|*" OR span="*&*" OR span="*`*")