CVE-2023-37859
📋 TL;DR
This vulnerability allows remote attackers with knowledge of the SNMPv2 read/write community string to execute arbitrary system commands with root privileges on affected PHOENIX CONTACT web panels. It affects WP 6xxx series web panels running versions prior to 4.0.10. Attackers can achieve complete system compromise through this SNMP privilege escalation flaw.
💻 Affected Systems
- PHOENIX CONTACT WP 6xxx series web panels
📦 What is this software?
Wp 6070 Wvps Firmware by Phoenixcontact
Wp 6101 Wxps Firmware by Phoenixcontact
Wp 6121 Wxps Firmware by Phoenixcontact
Wp 6156 Whps Firmware by Phoenixcontact
Wp 6185 Whps Firmware by Phoenixcontact
Wp 6215 Whps Firmware by Phoenixcontact
⚠️ Risk & Real-World Impact
Worst Case
Complete system takeover with root access, allowing installation of persistent backdoors, data theft, system destruction, or use as a pivot point into other network segments.
Likely Case
Unauthorized command execution leading to service disruption, configuration changes, credential harvesting, or lateral movement within the network.
If Mitigated
Limited impact if SNMP access is properly restricted through network controls and strong community strings, though the underlying vulnerability remains.
🎯 Exploit Status
Exploitation requires SNMPv2 community string knowledge but is straightforward once obtained. SNMP community strings are often weak or default in industrial environments.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 4.0.10
Vendor Advisory: https://cert.vde.com/en/advisories/VDE-2023-018/
Restart Required: Yes
Instructions:
1. Download firmware version 4.0.10 from PHOENIX CONTACT support portal. 2. Backup current configuration. 3. Upload and install firmware update via web interface. 4. Reboot device. 5. Verify version shows 4.0.10.
🔧 Temporary Workarounds
Restrict SNMP Access
linuxBlock SNMP traffic at network perimeter and only allow from trusted management stations.
iptables -A INPUT -p udp --dport 161 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p udp --dport 161 -j DROP
Change SNMP Community Strings
allReplace default or weak SNMP community strings with strong, unique values.
snmp-set community-string NEW_STRING
🧯 If You Can't Patch
- Isolate affected devices in separate VLAN with strict access controls.
- Disable SNMP service entirely if not required for monitoring.
🔍 How to Verify
Check if Vulnerable:
Check web panel firmware version via web interface or SNMP query. If version is below 4.0.10, device is vulnerable.Check Version:
snmpget -v2c -c COMMUNITY_STRING DEVICE_IP .1.3.6.1.2.1.1.1.0Verify Fix Applied:
Confirm firmware version shows 4.0.10 in web interface and test SNMP command execution attempts fail.📡 Detection & Monitoring
Log Indicators:
- Unusual SNMP write operations
- Failed SNMP authentication attempts
- Unexpected system command execution logs
Network Indicators:
- SNMP traffic from unexpected sources
- SNMP SET operations containing command strings
- Outbound connections from web panels to unusual destinations
SIEM Query:
source="snmpd" AND (command="*" OR exec="*")