Detection rules › Elastic
Scriptlet Execution via Rundll32
Identifies when scrobj.dll is loaded into rundll32.exe. An adversary may abuse rundll32.exe to proxy execution of malicious code.
MITRE ATT&CK coverage
Rule body
[rule]
description = """
Identifies when scrobj.dll is loaded into rundll32.exe. An adversary may abuse rundll32.exe to proxy execution of
malicious code.
"""
id = "93438ae3-becd-43fa-81de-645ce17afa8e"
license = "Elastic License v2"
name = "Scriptlet Execution via Rundll32"
os_list = ["windows"]
reference = [
"https://lolbas-project.github.io/lolbas/Libraries/Ieadvpack/",
"https://lolbas-project.github.io/lolbas/Libraries/Advpack/",
]
version = "1.0.30"
query = '''
sequence by process.entity_id with maxspan=1m
[process where event.action == "start" and process.pe.original_file_name == "RUNDLL32.EXE" and
process.command_line : "*advpack*LaunchINFSection*"]
[library where dll.name : "scrobj.dll"]
'''
min_endpoint_version = "7.15.0"
optional_actions = []
[[actions]]
action = "kill_process"
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 = "T1218.011"
name = "Rundll32"
reference = "https://attack.mitre.org/techniques/T1218/011/"
[threat.tactic]
id = "TA0005"
name = "Defense Evasion"
reference = "https://attack.mitre.org/tactics/TA0005/"
[internal]
min_endpoint_version = "7.15.0"
Stages and Predicates
Ordered sequence: each step below must occur in order within 1m, correlated by process.entity_id.
Stage 1: process
[process where event.action == "start" and process.pe.original_file_name == "RUNDLL32.EXE" and
process.command_line : "*advpack*LaunchINFSection*"]
Stage 2: library
[library where dll.name : "scrobj.dll"]
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
dll.name | wildcard |
| field:"dll.name" kind:wildcard value:"scrobj.dll" |
event.action | eq |
| field:"EventType" kind:eq value:"start" |
process.command_line | wildcard |
| field:"CommandLine" kind:wildcard value:"*advpack*LaunchINFSection*" |
process.pe.original_file_name | eq |
| field:"OriginalFileName" kind:eq value:"RUNDLL32.EXE" |