TCP Port 8121 – apollo-data

About TCP Port 8121

Port 8121 is registered with the Internet Assigned Numbers Authority (IANA) for apollo-data. The IANA description reads: ‘Apollo Data Port’. This port is referenced in 1 IDS rule and exhibits low malware activity in monitored traffic.

IDS Rule References

1 IDS / security rule reference TCP port 8121. 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 1): command-and-control (1).

Sample rule descriptions for TCP port 8121:

• ET MALWARE Win32/RaaLoader CnC Activity

Malware Rule References

A small share of the IDS rules that reference this port are malware related.

1 of the 1 IDS rule that reference TCP port 8121 are malware related. That describes detection coverage across the whole internet, not anything about your machine or your network.

Families observed (top 1): RaaLoader (1).

Data Sources

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