Empire Stager Execution

[rule]
description = """
Identifies when a script interpreter executes a base64-encoded Empire stager. Empire is penetration testing software
that is often utilized by attackers.
"""
id = "b7974ff6-82ff-4743-9e07-1c6901b1f0ea"
license = "Elastic License v2"
name = "Empire Stager Execution"
os_list = ["linux", "macos"]
reference = ["https://github.com/EmpireProject/Empire", "https://github.com/BC-SECURITY/Empire"]
version = "1.0.31"

query = '''
process where event.type == "start" and event.action == "exec" and
process.name like ("python*", "osascript", "sh", "bash", "dash", "ksh", "tcsh", "zsh") and
process.command_line like~ "*exec(base64.b64decode*aW1wb3J0IHN5cztpbXBvcnQg*"
'''

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 = "T1059"
name = "Command and Scripting Interpreter"
reference = "https://attack.mitre.org/techniques/T1059/"
[[threat.technique.subtechnique]]
id = "T1059.004"
name = "Unix Shell"
reference = "https://attack.mitre.org/techniques/T1059/004/"

[[threat.technique.subtechnique]]
id = "T1059.006"
name = "Python"
reference = "https://attack.mitre.org/techniques/T1059/006/"



[threat.tactic]
id = "TA0002"
name = "Execution"
reference = "https://attack.mitre.org/tactics/TA0002/"
[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1132"
name = "Data Encoding"
reference = "https://attack.mitre.org/techniques/T1132/"
[[threat.technique.subtechnique]]
id = "T1132.001"
name = "Standard Encoding"
reference = "https://attack.mitre.org/techniques/T1132/001/"



[threat.tactic]
id = "TA0011"
name = "Command and Control"
reference = "https://attack.mitre.org/tactics/TA0011/"

[internal]
min_endpoint_version = "7.15.0"