Unexpected Child Process of macOS Screensaver Engine

[rule]
description = """
Identifies when a child process is spawned by the screensaver engine process, which is consistent with an attacker's
malicious payload being executed after the screensaver activated on the endpoint. An adversary can maintain persistence
on a macOS endpoint by creating a malicious screensaver (.saver) file and configuring the screensaver plist file to
execute code each time the screensaver is activated.
"""
id = "fba012f6-7aa8-448e-8f59-cdecce2845b5"
license = "Elastic License v2"
name = "Unexpected Child Process of macOS Screensaver Engine"
os_list = ["macos"]
reference = [
    "https://posts.specterops.io/saving-your-access-d562bf5bf90b",
    "https://github.com/D00MFist/PersistentJXA",
]
version = "1.0.29"

query = '''
process where event.action == "exec" and process.parent.name == "ScreenSaverEngine"
'''

min_endpoint_version = "8.10.2"
optional_actions = []
[[actions]]
action = "kill_process"
field = "process.entity_id"
state = 0

[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1546"
name = "Event Triggered Execution"
reference = "https://attack.mitre.org/techniques/T1546/"
[[threat.technique.subtechnique]]
id = "T1546.002"
name = "Screensaver"
reference = "https://attack.mitre.org/techniques/T1546/002/"



[threat.tactic]
id = "TA0003"
name = "Persistence"
reference = "https://attack.mitre.org/tactics/TA0003/"

[internal]
min_endpoint_version = "8.10.2"