Microsoft Build Engine Started by a System Process

 1[metadata]
 2creation_date = "2020/03/25"
 3integration = ["endpoint", "windows"]
 4maturity = "production"
 5min_stack_comments = "New fields added: required_fields, related_integrations, setup"
 6min_stack_version = "8.3.0"
 7updated_date = "2024/03/28"
 8
 9[rule]
10author = ["Elastic"]
11description = """
12An instance of MSBuild, the Microsoft Build Engine, was started by Explorer or the WMI (Windows Management
13Instrumentation) subsystem. This behavior is unusual and is sometimes used by malicious payloads.
14"""
15false_positives = ["The Build Engine is commonly used by Windows developers but use by non-engineers is unusual."]
16from = "now-9m"
17index = ["winlogbeat-*", "logs-endpoint.events.process-*", "logs-windows.*", "endgame-*", "logs-system.security*"]
18language = "eql"
19license = "Elastic License v2"
20name = "Microsoft Build Engine Started by a System Process"
21risk_score = 47
22rule_id = "9d110cb3-5f4b-4c9a-b9f5-53f0a1707ae3"
23setup = """## Setup
24
25If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2,
26events will not define `event.ingested` and default fallback for EQL rules was not added until version 8.2.
27Hence for this rule to work effectively, users will need to add a custom ingest pipeline to populate
28`event.ingested` to @timestamp.
29For more details on adding a custom ingest pipeline refer - https://www.elastic.co/guide/en/fleet/current/data-streams-pipeline-tutorial.html
30"""
31severity = "medium"
32tags = ["Domain: Endpoint",
33        "OS: Windows",
34        "Use Case: Threat Detection",
35        "Tactic: Defense Evasion",
36        "Tactic: Execution",
37        "Data Source: Elastic Endgame",
38        "Data Source: Elastic Defend"
39        ]
40timestamp_override = "event.ingested"
41type = "eql"
42
43query = '''
44process where host.os.type == "windows" and event.type == "start" and
45  process.name : "MSBuild.exe" and
46  process.parent.name : ("explorer.exe", "wmiprvse.exe")
47'''
48
49
50[[rule.threat]]
51framework = "MITRE ATT&CK"
52[[rule.threat.technique]]
53id = "T1127"
54name = "Trusted Developer Utilities Proxy Execution"
55reference = "https://attack.mitre.org/techniques/T1127/"
56[[rule.threat.technique.subtechnique]]
57id = "T1127.001"
58name = "MSBuild"
59reference = "https://attack.mitre.org/techniques/T1127/001/"
60
61
62
63[rule.threat.tactic]
64id = "TA0005"
65name = "Defense Evasion"
66reference = "https://attack.mitre.org/tactics/TA0005/"
67[[rule.threat]]
68framework = "MITRE ATT&CK"
69
70[rule.threat.tactic]
71id = "TA0002"
72name = "Execution"
73reference = "https://attack.mitre.org/tactics/TA0002/"