Potential Protocol Tunneling via Chisel Server
editPotential Protocol Tunneling via Chisel Server
editThis rule monitors for common command line flags leveraged by the Chisel server utility followed by a received connection within a timespan of 1 minute. Chisel is a command-line utility used for creating and managing TCP and UDP tunnels, enabling port forwarding and secure communication between machines. Attackers can abuse the Chisel utility to establish covert communication channels, bypass network restrictions, and carry out malicious activities by creating tunnels that allow unauthorized access to internal systems.
Rule type: eql
Rule indices:
- logs-endpoint.events.*
Severity: medium
Risk score: 47
Runs every: 5m
Searches indices from: now-9m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References:
Tags:
- Domain: Endpoint
- OS: Linux
- Use Case: Threat Detection
- Tactic: Command and Control
- Data Source: Elastic Defend
Version: 3
Rule authors:
- Elastic
Rule license: Elastic License v2
Rule query
editsequence by host.id, process.entity_id with maxspan=1m
[process where host.os.type == "linux" and event.action == "exec" and event.type == "start" and
process.args == "server" and process.args in ("--port", "-p", "--reverse", "--backend", "--socks5") and
process.args_count >= 3 and process.parent.name in ("bash", "dash", "ash", "sh", "tcsh", "csh", "zsh", "ksh", "fish")]
[network where host.os.type == "linux" and event.action == "connection_accepted" and event.type == "start" and
destination.ip != null and destination.ip != "127.0.0.1" and destination.ip != "::1" and
not process.name : (
"python*", "php*", "perl", "ruby", "lua*", "openssl", "nc", "netcat", "ncat", "telnet", "awk", "java", "telnet",
"ftp", "socat", "curl", "wget", "dpkg", "docker", "dockerd", "yum", "apt", "rpm", "dnf", "ssh", "sshd", "hugo")]
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Command and Control
- ID: TA0011
- Reference URL: https://attack.mitre.org/tactics/TA0011/
-
Technique:
- Name: Protocol Tunneling
- ID: T1572
- Reference URL: https://attack.mitre.org/techniques/T1572/