TCP Port 113 – auth

About TCP Port 113

Port 113 carries the IANA assignment for auth. The IANA description reads: ‘Authentication Service’. This port appears in 2 IDS rules and does not have notable malware activity indicators in our data.

IDS Rule References

2 IDS / security rules reference TCP port 113. Treat that number as context, not a danger score. Many detection rules are written against groups of ports rather than one service, web ports especially, so common web alternate ports inherit large counts while genuinely sensitive services can show few rules or none. Presence in IDS rules does not mean traffic on this port is malicious.

Rule categories (top 2): attempted-recon (1), attempted-admin (1).

Sample rule descriptions for TCP port 113:

• INDICATOR-SCAN ident version request
• SERVER-MAIL Sendmail 8.6.9 exploit

Data Sources

This information is compiled from: IANA Service Name and Transport Protocol Port Number Registry and Snort Community Rules (GPLv2).