Suspicious Registry Symbolic Link

[rule]
description = """
Identifies the creation of registry symbolic link by an unusual process. This may indicate an attempt to elevate
privileges via hijacking privileged registry read operations using a malicious registry symbolic link.
"""
id = "0c5c8b29-9903-4a04-9ca8-20abafc9db41"
license = "Elastic License v2"
name = "Suspicious Registry Symbolic Link"
os_list = ["windows"]
version = "1.0.10"

query = '''
registry where event.action == "modification" and user.id : ("S-1-5-21*", "S-1-12-*") and
registry.value : "SymbolicLinkValue" and process.executable : "?:\\*" and
 not process.executable :
            ("?:\\Windows\\System32\\DriverStore\\FileRepository\\*", 
	     "?:\\Windows\\System32\\svchost.exe", 
             "?:\\Program Files\\*.exe", 
	     "?:\\Program Files (x86)\\*.exe", 
             "?:\\Windows\\Temp\\asw-*\\avg-av\\icarus.exe", 
	     "?:\\$WINDOWS.~BT\\Work\\*\\DismHost.exe") and
 not (process.code_signature.trusted == true and not process.code_signature.subject_name : "Microsoft*") and
 not (process.name : "DismHost.exe" and process.code_signature.trusted == true and process.code_signature.subject_name : "Microsoft *") and
 not (process.executable : "?:\\Windows\\System32\\msiexec.exe" and registry.path : "HKEY_USERS\\*\\Software\\Nico Mak Computing\\SymbolicLinkValue")
'''

actions = []
min_endpoint_version = "8.4.0"
[[optional_actions]]
action = "rollback"
field = "process.entity_id"
state = 0

[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1574"
name = "Hijack Execution Flow"
reference = "https://attack.mitre.org/techniques/T1574/"


[threat.tactic]
id = "TA0004"
name = "Privilege Escalation"
reference = "https://attack.mitre.org/tactics/TA0004/"
[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1112"
name = "Modify Registry"
reference = "https://attack.mitre.org/techniques/T1112/"


[threat.tactic]
id = "TA0005"
name = "Defense Evasion"
reference = "https://attack.mitre.org/tactics/TA0005/"

[internal]
min_endpoint_version = "8.4.0"