UDP Port 25 – SMTP (Simple Mail Transfer Protocol)

About UDP Port 25

The Internet Assigned Numbers Authority (IANA) registers port 25 for smtp. The IANA description reads: ‘Simple Mail Transfer’. This port does not currently appear in the IDS rulesets or malware activity indicators in our data sources.

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), Snort Community Rules (GPLv2), and MITRE ATT&CK (Apache 2.0).