[rule]
description = """
This rule monitors for attempts to clear logs using the "journalctl" command on Linux systems. Adversaries may use this
technique to cover their tracks by deleting or truncating log files, making it harder for defenders to investigate their
activities. The rule looks for the execution of "journalctl" with arguments that indicate log clearing actions, such as
"--vacuum-time", "--vacuum-size", or "--vacuum-files".
"""
id = "2f45b36f-a60d-46c9-9f82-eb80ab62ce7f"
license = "Elastic License v2"
name = "Attempt to Clear Logs via Journalctl"
os_list = ["linux"]
version = "1.0.1"
query = '''
process where event.type == "start" and event.action == "exec" and process.name == "journalctl" and
process.args like~ ("--vacuum-time=?s", "--vacuum-size=?M", "--vacuum-files=*") and
not (
process.parent.args in ("/usr/lib/armbian/armbian-truncate-logs", "/root/innovasive_reverseproxy/backupscript/cleanup_hour.sh") or
process.parent.executable == "/tmp/newroot/usr/bin/sudo"
)
'''
min_endpoint_version = "7.15.0"
optional_actions = []
[[actions]]
action = "kill_process"
field = "process.entity_id"
state = 0
[[actions]]
action = "kill_process"
field = "process.parent.entity_id"
state = 0
[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1070"
name = "Indicator Removal"
reference = "https://attack.mitre.org/techniques/T1070/"
[[threat.technique.subtechnique]]
id = "T1070.002"
name = "Clear Linux or Mac System Logs"
reference = "https://attack.mitre.org/techniques/T1070/002/"
[[threat.technique]]
id = "T1562"
name = "Impair Defenses"
reference = "https://attack.mitre.org/techniques/T1562/"
[[threat.technique.subtechnique]]
id = "T1562.001"
name = "Disable or Modify Tools"
reference = "https://attack.mitre.org/techniques/T1562/001/"
[threat.tactic]
id = "TA0005"
name = "Defense Evasion"
reference = "https://attack.mitre.org/tactics/TA0005/"
[internal]
min_endpoint_version = "7.15.0"