[metadata] creation_date = "2023/09/04" integration = ["endpoint"] maturity = "production" min_stack_comments = "New fields added: required_fields, related_integrations, setup" min_stack_version = "8.3.0" updated_date = "2023/09/04" [rule] author = ["Elastic"] description = """ This rule monitors for the execution of the cat command, followed by a connection attempt by the same process. Cat is capable of transfering data via tcp/udp channels by redirecting its read output to a /dev/tcp or /dev/udp channel. This activity is highly suspicious, and should be investigated. Attackers may leverage this capability to transfer tools or files to another host in the network or exfiltrate data while attempting to evade detection in the process. """ from = "now-9m" index = ["logs-endpoint.events.*"] language = "eql" license = "Elastic License v2" name = "Network Activity Detected via cat" risk_score = 47 rule_id = "afd04601-12fc-4149-9b78-9c3f8fe45d39" severity = "medium" tags = ["Domain: Endpoint", "OS: Linux", "Use Case: Threat Detection", "Tactic: Command and Control", "Data Source: Elastic Defend"] type = "eql" query = ''' sequence by host.id, process.entity_id with maxspan=1s [process where host.os.type == "linux" and event.action == "exec" and event.type == "start" and process.name == "cat"] [network where host.os.type == "linux" and event.action in ("connection_attempted", "disconnect_received") and process.name == "cat"] ''' [[rule.threat]] framework = "MITRE ATT&CK" [rule.threat.tactic] id = "TA0011" name = "Command and Control" reference = "https://attack.mitre.org/tactics/TA0011/" [[rule.threat]] framework = "MITRE ATT&CK" [rule.threat.tactic] id = "TA0005" name = "Defense Evasion" reference = "https://attack.mitre.org/tactics/TA0005/" [[rule.threat]] framework = "MITRE ATT&CK" [rule.threat.tactic] id = "TA0010" name = "Exfiltration" reference = "https://attack.mitre.org/tactics/TA0010/"