UDP Port 161 – SNMP (Simple Network Management Protocol)

About UDP Port 161

Port 161 carries the IANA assignment for snmp. The IANA description reads: ‘SNMP’. This port appears in 14 IDS rules and does not have notable malware activity indicators in our data.

IDS Rule References

14 IDS / security rules reference UDP port 161. Presence in IDS rules does not mean traffic on this port is malicious. These are patterns security tools monitor.

Rule categories (top 4): misc-attack (6), attempted-recon (5), attempted-admin (2), attempted-dos (1).

Sample rule descriptions for UDP port 161:

• SERVER-OTHER Bay/Nortel Nautica Marlin
• PROTOCOL-SNMP NT UserList
• PROTOCOL-SNMP community string buffer overflow attempt
• PROTOCOL-SNMP public access udp
• PROTOCOL-SNMP private access udp

Data Sources

This information is compiled from: IANA Service Name and Transport Protocol Port Number Registry, Emerging Threats Open Ruleset (BSD 2-Clause / GPLv2 per SID range), and Snort Community Rules (GPLv2).