Persistence via Microsoft Outlook VBA

 1[metadata]
 2creation_date = "2020/11/23"
 3integration = ["endpoint", "windows", "m365_defender", "sentinel_one_cloud_funnel"]
 4maturity = "production"
 5updated_date = "2024/10/15"
 6min_stack_version = "8.14.0"
 7min_stack_comments = "Breaking change at 8.14.0 for the Windows Integration."
 8
 9[rule]
10author = ["Elastic"]
11description = "Detects attempts to establish persistence on an endpoint by installing a rogue Microsoft Outlook VBA Template."
12false_positives = ["A legitimate VBA for Outlook is usually configured interactively via OUTLOOK.EXE."]
13from = "now-9m"
14index = ["logs-endpoint.events.file-*", "winlogbeat-*", "logs-windows.sysmon_operational-*", "endgame-*", "logs-m365_defender.event-*", "logs-sentinel_one_cloud_funnel.*"]
15language = "eql"
16license = "Elastic License v2"
17name = "Persistence via Microsoft Outlook VBA"
18references = [
19    "https://www.mdsec.co.uk/2020/11/a-fresh-outlook-on-mail-based-persistence/",
20    "https://www.linkedin.com/pulse/outlook-backdoor-using-vba-samir-b-/",
21]
22risk_score = 47
23rule_id = "397945f3-d39a-4e6f-8bcb-9656c2031438"
24severity = "medium"
25tags = [
26    "Domain: Endpoint",
27    "OS: Windows",
28    "Use Case: Threat Detection",
29    "Tactic: Persistence",
30    "Data Source: Elastic Endgame",
31    "Data Source: Elastic Defend",
32    "Data Source: Sysmon",
33    "Data Source: Microsoft Defender for Endpoint",
34    "Data Source: SentinelOne",
35]
36timestamp_override = "event.ingested"
37type = "eql"
38
39query = '''
40file where host.os.type == "windows" and event.type != "deletion" and
41 file.path : "C:\\Users\\*\\AppData\\Roaming\\Microsoft\\Outlook\\VbaProject.OTM"
42'''
43
44
45[[rule.threat]]
46framework = "MITRE ATT&CK"
47[[rule.threat.technique]]
48id = "T1137"
49name = "Office Application Startup"
50reference = "https://attack.mitre.org/techniques/T1137/"
51
52
53[rule.threat.tactic]
54id = "TA0003"
55name = "Persistence"
56reference = "https://attack.mitre.org/tactics/TA0003/"