Remote XSL Script Execution via COM

 1[metadata]
 2creation_date = "2023/09/27"
 3integration = ["endpoint"]
 4maturity = "production"
 5min_stack_comments = "New fields added: required_fields, related_integrations, setup"
 6min_stack_version = "8.3.0"
 7updated_date = "2024/04/08"
 8
 9[rule]
10author = ["Elastic"]
11description = """
12Identifies the execution of a hosted XSL script using the Microsoft.XMLDOM COM interface via Microsoft Office processes. 
13This behavior may indicate adversarial activity to execute malicious JScript or VBScript on the system.
14"""
15from = "now-9m"
16index = ["logs-endpoint.events.process-*", "logs-endpoint.events.library-*"]
17language = "eql"
18license = "Elastic License v2"
19name = "Remote XSL Script Execution via COM"
20risk_score = 21
21rule_id = "48f657ee-de4f-477c-aa99-ed88ee7af97a"
22severity = "low"
23tags = ["Domain: Endpoint", "OS: Windows", "Use Case: Threat Detection", "Tactic: Initial Access", "Tactic: Defense Evasion", "Data Source: Elastic Defend"]
24type = "eql"
25
26query = '''
27sequence with maxspan=1m
28 [library where host.os.type == "windows" and dll.name : "msxml3.dll" and
29  process.name : ("winword.exe", "excel.exe", "powerpnt.exe", "mspub.exe")] by process.entity_id
30 [process where host.os.type == "windows" and event.action == "start" and
31  process.parent.name : ("winword.exe", "excel.exe", "powerpnt.exe", "mspub.exe") and 
32  not process.executable :
33        ("?:\\Windows\\System32\\WerFault.exe",
34         "?:\\Windows\\SysWoW64\\WerFault.exe",
35         "?:\\windows\\splwow64.exe",
36         "?:\\Windows\\System32\\conhost.exe",
37         "?:\\Program Files\\*.exe",
38         "?:\\Program Files (x86)\\*exe")] by process.parent.entity_id
39'''
40
41[[rule.threat]]
42framework = "MITRE ATT&CK"
43[[rule.threat.technique]]
44id = "T1566"
45name = "Phishing"
46reference = "https://attack.mitre.org/techniques/T1566/"
47[[rule.threat.technique.subtechnique]]
48id = "T1566.002"
49name = "Spearphishing Link"
50reference = "https://attack.mitre.org/techniques/T1566/002/"
51
52
53
54[rule.threat.tactic]
55id = "TA0001"
56name = "Initial Access"
57reference = "https://attack.mitre.org/tactics/TA0001/"
58
59[[rule.threat]]
60framework = "MITRE ATT&CK"
61[[rule.threat.technique]]
62id = "T1220"
63name = "XSL Script Processing"
64reference = "https://attack.mitre.org/techniques/T1220/"
65
66
67[rule.threat.tactic]
68id = "TA0005"
69name = "Defense Evasion"
70reference = "https://attack.mitre.org/tactics/TA0005/"