M365 Portal Login (Impossible Travel)

  1[metadata]
  2creation_date = "2024/09/04"
  3integration = ["o365"]
  4maturity = "production"
  5updated_date = "2025/09/08"
  6
  7[rule]
  8author = ["Elastic"]
  9description = """
 10Detects successful Microsoft 365 portal logins from impossible travel locations. Impossible travel locations are defined
 11as two different countries within a short time frame. This behavior may indicate an adversary attempting to access a
 12Microsoft 365 account from a compromised account or a malicious actor attempting to access a Microsoft 365 account from
 13a different location.
 14"""
 15false_positives = [
 16    """
 17    False positives may occur when users are using a VPN or when users are traveling to different locations for
 18    legitimate purposes.
 19    """,
 20]
 21from = "now-15m"
 22index = ["logs-o365.audit-*"]
 23language = "kuery"
 24license = "Elastic License v2"
 25name = "M365 Portal Login (Impossible Travel)"
 26note = """## Triage and analysis
 27
 28### Investigating M365 Portal Login (Impossible Travel)
 29
 30Microsoft 365's cloud-based services enable global access, but this can be exploited by adversaries logging in from disparate locations within short intervals, indicating potential account compromise. The detection rule identifies such anomalies by analyzing login events for rapid geographic shifts, flagging suspicious activity that may suggest unauthorized access attempts.
 31
 32### Possible investigation steps
 33
 34- Review the user associated with these sign-ins to determine if the login attempt was legitimate or if further investigation is needed.
 35- Analyze the geographic locations of the logins to identify any patterns or anomalies that may indicate malicious activity.
 36- Review the ISP information for the login attempts to identify any unusual or suspicious providers.
 37- Review the authorization request type to understand the context of the login attempts and whether they align with the user's typical behavior.
 38- Analyze the client application used for the login attempts to determine if it is consistent with the user's normal usage patterns (Teams, Office, etc.)
 39- Analyze the user-agent associated with the login attempts to identify any unusual or suspicious patterns.
 40
 41### False positive analysis
 42
 43- Users traveling or using VPNs may trigger this alert. Verify with the user if they were traveling or using a VPN at the time of the login attempt.
 44- Mobile access may also result in false positives, as users may log in from various locations while on the go.
 45
 46### Response and remediation
 47
 48- Investigate the login attempt further by checking for any additional context or related events that may provide insight into the user's behavior.
 49- If the login attempt is deemed suspicious, consider implementing additional security measures, such as requiring multi-factor authentication (MFA) for logins from unusual locations.
 50- Educate users about the risks of accessing corporate resources from unfamiliar locations and the importance of using secure connections (e.g., VPNs) when doing so.
 51- Monitor for any subsequent login attempts from the same location or IP address to identify potential patterns of malicious activity.
 52"""
 53references = ["https://www.huntress.com/blog/time-travelers-busted-how-to-detect-impossible-travel-"]
 54risk_score = 47
 55rule_id = "3896d4c0-6ad1-11ef-8c7b-f661ea17fbcc"
 56severity = "medium"
 57tags = [
 58    "Domain: Cloud",
 59    "Domain: SaaS",
 60    "Data Source: Microsoft 365",
 61    "Data Source: Microsoft 365 Audit Logs",
 62    "Use Case: Threat Detection",
 63    "Use Case: Identity and Access Audit",
 64    "Tactic: Initial Access",
 65    "Resources: Investigation Guide",
 66]
 67timestamp_override = "event.ingested"
 68type = "threshold"
 69
 70query = '''
 71event.dataset:o365.audit and
 72    event.provider:AzureActiveDirectory and
 73    event.action:UserLoggedIn and
 74    event.outcome:success and
 75    o365.audit.Target.Type:(0 or 10 or 2 or 3 or 5 or 6) and
 76    o365.audit.UserId:(* and not "Not Available") and
 77    source.geo.country_name:* and
 78    o365.audit.Target.ID:(
 79        00000006-0000-0ff1-ce00-000000000000 or
 80        4765445b-32c6-49b0-83e6-1d93765276ca
 81    ) and not o365.audit.ApplicationId:(
 82        29d9ed98-a469-4536-ade2-f981bc1d605e or
 83        38aa3b87-a06d-4817-b275-7a316988d93b or
 84        a809996b-059e-42e2-9866-db24b99a9782
 85    ) and not o365.audit.ExtendedProperties.RequestType:(
 86        "Cmsi:Cmsi" or
 87        "Consent:Set" or
 88        "Login:reprocess" or
 89        "Login:resume" or
 90        "MessagePrompt:MessagePrompt" or
 91        "SAS:EndAuth"
 92    )
 93'''
 94
 95
 96[[rule.threat]]
 97framework = "MITRE ATT&CK"
 98[[rule.threat.technique]]
 99id = "T1078"
100name = "Valid Accounts"
101reference = "https://attack.mitre.org/techniques/T1078/"
102[[rule.threat.technique.subtechnique]]
103id = "T1078.004"
104name = "Cloud Accounts"
105reference = "https://attack.mitre.org/techniques/T1078/004/"
106
107
108
109[rule.threat.tactic]
110id = "TA0001"
111name = "Initial Access"
112reference = "https://attack.mitre.org/tactics/TA0001/"
113
114[rule.investigation_fields]
115field_names = [
116    "@timestamp",
117    "organization.id",
118    "o365.audit.UserId",
119    "o365.audit.ActorIpAddress",
120    "o365.audit.ApplicationId",
121    "o365.audit.ExtendedProperties.RequestType",
122    "o365.audit.Target.ID",
123    "source.geo.country_name",
124]
125
126[rule.threshold]
127field = ["o365.audit.UserId"]
128value = 1
129[[rule.threshold.cardinality]]
130field = "source.geo.country_name"
131value = 2