IPSEC NAT Traversal Port Activityedit
Detects events that could be describing IPSEC NAT Traversal traffic. IPSEC is a VPN technology that allows one system to talk to another using encrypted tunnels. NAT Traversal enables these tunnels to communicate over the Internet where one of the sides is behind a NAT router gateway. This may be common on your network, but this technique is also used by threat actors to avoid detection.
Rule type: query
Rule indices:
- filebeat-*
- packetbeat-*
Severity: low
Risk score: 21
Runs every: 5 minutes
Searches indices from: now-6m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
Tags:
- Elastic
- Network
Version: 3 (version history)
Added (Elastic Stack release): 7.6.0
Last modified (Elastic Stack release): 7.9.0
Rule authors: Elastic
Rule license: Elastic License
Potential false positivesedit
Some networks may utilize these protocols but usage that is unfamiliar to local network administrators can be unexpected and suspicious. Because this port is in the ephemeral range, this rule may false under certain conditions, such as when an application server with a public IP address replies to a client which has used a UDP port in the range by coincidence. This is uncommon but such servers can be excluded.
Rule queryedit
event.category:(network or network_traffic) and network.transport:udp and destination.port:4500
Threat mappingedit
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Command and Control
- ID: TA0011
- Reference URL: https://attack.mitre.org/tactics/TA0011/
-
Technique:
- Name: Commonly Used Port
- ID: T1043
- Reference URL: https://attack.mitre.org/techniques/T1043/
Rule version historyedit
- Version 3 (7.9.0 release)
-
-
Updated query, changed from:
network.transport:udp and destination.port:4500
-
- Version 2 (7.6.1 release)
-
- Removed auditbeat-*, packetbeat-*, and winlogbeat-* from the rule indices.