Scriptlet Execution via CMSTP


Description

Identifies when scrobj.dll is loaded into the Microsoft Connection Manager Profile Installer (cmstp.exe) process. This may indicate an attempt to bypass application whitelisting by executing a malicious scriptlet in a trusted process.

Query · eql

sequence by process.entity_id with maxspan=1m
 [process where event.action == "start" and process.pe.original_file_name == "CMSTP.EXE"]
 [library where dll.name : "scrobj.dll"]
Raw source Scriptlet Execution via CMSTP · Elastic TOML
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Published by elastic/protections-artifacts ↗, licensed under Elastic License 2.0 ↗. Reproduced here unmodified.
[rule]
description = """
Identifies when scrobj.dll is loaded into the Microsoft Connection Manager Profile Installer (cmstp.exe) process. This
may indicate an attempt to bypass application whitelisting by executing a malicious scriptlet in a trusted process.
"""
id = "8adfa9ad-0ed2-4b1b-bdad-f2c52e1d2a00"
license = "Elastic License v2"
name = "Scriptlet Execution via CMSTP"
os_list = ["windows"]
reference = ["https://lolbas-project.github.io/lolbas/Binaries/Cmstp/"]
version = "1.0.31"

query = '''
sequence by process.entity_id with maxspan=1m
 [process where event.action == "start" and process.pe.original_file_name == "CMSTP.EXE"]
 [library where dll.name : "scrobj.dll"]
'''

min_endpoint_version = "7.15.0"
[[actions]]
action = "kill_process"
field = "process.entity_id"
state = 0

[[optional_actions]]
action = "rollback"
field = "process.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 = "T1059.005"
name = "Visual Basic"
reference = "https://attack.mitre.org/techniques/T1059/005/"

[[threat.technique.subtechnique]]
id = "T1059.007"
name = "JavaScript"
reference = "https://attack.mitre.org/techniques/T1059/007/"



[threat.tactic]
id = "TA0002"
name = "Execution"
reference = "https://attack.mitre.org/tactics/TA0002/"
[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1218"
name = "System Binary Proxy Execution"
reference = "https://attack.mitre.org/techniques/T1218/"
[[threat.technique.subtechnique]]
id = "T1218.003"
name = "CMSTP"
reference = "https://attack.mitre.org/techniques/T1218/003/"



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

[internal]
min_endpoint_version = "7.15.0"

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