LoFP LoFP / false-positives (fp) can appear if another remote terminal service is being used to connect to it's listener but typically ssh is used in these scenarios.

Techniques

Sample rules

Suspicious Network Connection Attempt by Root

Description

Identifies an outbound network connection attempt followed by a session id change as the root user by the same process entity. This particular instantiation of a network connection is abnormal and should be investigated as it may indicate a potential reverse shell activity via a privileged process.

Detection logic

sequence by process.entity_id with maxspan=1m
[network where host.os.type == "linux" and event.type == "start" and event.action == "connection_attempted" and user.id == "0" and
    not process.executable : ("/bin/ssh", "/sbin/ssh", "/usr/lib/systemd/systemd", "/usr/sbin/sshd","/usr/bin/ssh","/usr/bin/sshpass")]
[process where host.os.type == "linux" and event.action == "session_id_change" and user.id == "0" and
    not process.executable : ("/bin/ssh", "/sbin/ssh", "/usr/lib/systemd/systemd", "/usr/sbin/sshd","/usr/bin/ssh","/usr/bin/sshpass")]