BPF filter applied using TC

Detects when the tc (transmission control) binary is utilized to set a BPF (Berkeley Packet Filter) on a network interface. Tc is used to configure Traffic Control in the Linux kernel. It can shape, schedule, police, and drop traffic. A threat actor can utilize tc to set a BPF filter on an interface for the purpose of manipulating the incoming traffic. This technique is not at all common and should indicate abnormal, suspicious or malicious activity.

Rule type: eql

Rule indices:

Severity: high

Risk score: 73

Runs every: 5 minutes

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

Tags:

Last modified (Elastic Stack release): 8.4.0

Rule authors: Elastic

Rule license: Elastic License v2

process where event.type != "end" and process.executable :
"/usr/sbin/tc" and process.args : "filter" and process.args : "add"
and process.args : "bpf" and not process.parent.executable:
"/usr/sbin/libvirtd"