Elastic Security Detection Rules

File Transfer or Listener Established via Netcat

Last updated a month ago on 2025-10-15
Created 6 years ago on 2020-02-18

About

A netcat process is engaging in network activity on a Linux host. Netcat is often used as a persistence mechanism by exporting a reverse shell or by serving a shell on a listening port. Netcat is also sometimes used for data exfiltration.
Tags
Domain: EndpointOS: LinuxUse Case: Threat DetectionTactic: ExecutionData Source: Elastic DefendData Source: Elastic EndgameData Source: Auditd ManagerData Source: CrowdstrikeData Source: SentinelOneLanguage: eql
Severity
medium
Risk Score
47
MITRE ATT&CK™

Execution (TA0002)(opens in a new tab or window)

↳ Command and Scripting Interpreter (T1059)(opens in a new tab or window)

False Positive Examples
Netcat is a dual-use tool that can be used for benign or malicious activity. Netcat is included in some Linux distributions so its presence is not necessarily suspicious. Some normal use of this program, while uncommon, may originate from scripts, automation tools, and frameworks.
License
Elastic License v2(opens in a new tab or window)

Definition

Rule Type
Event Correlation Rule
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
auditbeat-*endgame-*logs-auditd_manager.auditd-*logs-crowdstrike.fdr*logs-endpoint.events.process*logs-sentinel_one_cloud_funnel.*
Related Integrations

endpoint(opens in a new tab or window)

auditd_manager(opens in a new tab or window)

crowdstrike(opens in a new tab or window)

sentinel_one_cloud_funnel(opens in a new tab or window)

Query
process where host.os.type == "linux" and event.type == "start" and
event.action in ("exec", "exec_event", "start", "ProcessRollup2", "executed", "process_started") and
process.name in ("nc","ncat","netcat","netcat.openbsd","netcat.traditional") and
process.args like~ (
  /* bind shell to specific port or listener */
  "-*l*","-*p*",
  /* reverse shell to command-line interpreter used for command execution */
  "-*e*",
  /* file transfer via stdout/pipe */
  ">","<", "|"
)

Install detection rules in Elastic Security

Detect File Transfer or Listener Established via Netcat in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(opens in a new tab or window).