CVE-2023-33274
📋 TL;DR
This vulnerability allows unauthenticated attackers to bypass authentication in PowerShield SNMP Web Pro 1.1 by directly accessing CGI scripts without proper cookie verification. All instances without HTTP Digest authentication enabled are affected regardless of password strength. This affects organizations using this specific SNMP monitoring software.
💻 Affected Systems
- PowerShield SNMP Web Pro
📦 What is this software?
Snmp Web Pro by Voltronicpower
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of SNMP monitoring system allowing unauthorized access to network device configurations, potential credential harvesting, and lateral movement to other systems.
Likely Case
Unauthorized access to SNMP monitoring interface allowing viewing of sensitive network information, configuration changes, and potential denial of service.
If Mitigated
Limited impact with proper network segmentation and monitoring, though authentication bypass remains possible.
🎯 Exploit Status
Exploitation requires direct HTTP requests to CGI scripts without authentication. Public proof-of-concept demonstrates the bypass technique.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Unknown
Restart Required: No
Instructions:
No official patch available. Enable HTTP Digest authentication as primary mitigation.
🔧 Temporary Workarounds
Enable HTTP Digest Authentication
allEnable HTTP Digest authentication in SNMP Web Pro configuration to enforce proper authentication.
Configure via web interface: Settings > Security > Enable HTTP Digest Authentication
Network Access Control
linuxRestrict access to SNMP Web Pro interface using firewall rules or network segmentation.
iptables -A INPUT -p tcp --dport [web_port] -s [trusted_networks] -j ACCEPT
iptables -A INPUT -p tcp --dport [web_port] -j DROP
🧯 If You Can't Patch
- Isolate SNMP Web Pro system in separate VLAN with strict access controls
- Implement web application firewall (WAF) rules to block unauthorized CGI script access
🔍 How to Verify
Check if Vulnerable:
Attempt to access CGI scripts directly without authentication: curl -v http://[target]/cgi-bin/*.cgiCheck Version:
Check web interface footer or about page for version informationVerify Fix Applied:
Verify HTTP Digest authentication is enabled and CGI scripts require proper authentication📡 Detection & Monitoring
Log Indicators:
- Unauthenticated access to CGI scripts
- Failed authentication attempts followed by successful CGI access
Network Indicators:
- HTTP requests to CGI scripts without authentication headers
- Unusual access patterns to SNMP monitoring interface
SIEM Query:
source="web_logs" AND (uri="/cgi-bin/*" OR uri="*.cgi") AND NOT (auth_status="success" OR cookie="*")