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id: e5f6a7b8-c9d0-4e1f-2a3b-4c5d6e7f8a9b
name: "SigninLogs — Off-Hours Sign-In by Privileged Account"
version: 1.0.0
kind: Scheduled
description: |
  Detects privileged accounts signing in between 22:00 and 05:00 UTC. Off-hours admin access is a key hunting signal for insider threats, living-off-the-land attackers, and compromised admin credentials. Investigate alongside concurrent AuditLogs activity. MITRE ATT&CK: T1078 (Valid Accounts), T1098 (Account Manipulation).
severity: Medium
requiredDataConnectors:
  - connectorId: AzureActiveDirectory
    dataTypes:
      - SigninLogs
queryFrequency: PT1H
queryPeriod: PT1H
triggerOperator: gt
triggerThreshold: 0
tactics:
  - InitialAccess
  - Persistence
relevantTechniques:
  - T1078
  - T1098
query: |

    // ---- Network Allowlist (exclude trusted IPs / CIDR / ranges) --------------
    let _allow = materialize(union isfuzzy=true (print R="" | take 0), (_GetWatchlist('NetworkAllowlist') | project R = tostring(IPOrRange)) | where isnotempty(R));
    let _allowCIDR  = toscalar(_allow | where not(R matches regex @'^\d+\.\d+\.\d+\.\d+-\d+\.\d+\.\d+\.\d+$') | extend R = iff(R has '/', R, strcat(R, '/32')) | summarize make_list(R));
    let _allowRange = toscalar(_allow | where R matches regex @'^\d+\.\d+\.\d+\.\d+-\d+\.\d+\.\d+\.\d+$' | summarize make_list(R));
    let _ExcludeAllowlistedIPs = (T:(IPAddress:string)) {
        T
        | extend IPAddress = tostring(IPAddress)
        | where array_length(_allowCIDR) == 0 or isnull(ipv4_is_in_any_range(IPAddress, _allowCIDR)) or not(ipv4_is_in_any_range(IPAddress, _allowCIDR))
        | mv-apply _r = _allowRange to typeof(string) on (
            extend _lo = tostring(split(_r,'-')[0]), _hi = tostring(split(_r,'-')[1])
            | extend _inRange = ipv4_compare(IPAddress, _lo) >= 0 and ipv4_compare(IPAddress, _hi) <= 0
            | summarize _anyInRange = max(toint(_inRange)))
        | where isnull(_anyInRange) or _anyInRange == 0
        | project-away _anyInRange
    };
    // ---------------------------------------------------------------------------
    let privilegedKeywords = dynamic([
        "admin", "adm-", "adm.", "-adm", "_adm",
        "da-", "ea-", "ga-", "pa-",
        "tier0", "tier-0", "t0-",
        "priv", "svc.adm", "svc-adm",
        "globaladmin", "secadmin", "cloudadmin"
    ]);
    let offHoursStart = 22;
    let offHoursEnd   = 5;
    SigninLogs
    | invoke _ExcludeAllowlistedIPs()
    | where TimeGenerated > ago(1h)
    | where ResultType == "0"
    | where UserPrincipalName has_any (privilegedKeywords)
    | extend HourOfDay = hourofday(TimeGenerated)
    | where HourOfDay >= offHoursStart or HourOfDay < offHoursEnd
    | project
        TimeGenerated, UserPrincipalName,
        IPAddress, Location,
        AppDisplayName, HourOfDay,
        RiskLevelDuringSignIn, ConditionalAccessStatus,
        IsInteractive
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: UserPrincipalName
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: IPAddress
customDetails:
  HourOfDay: HourOfDay
  AppDisplayName: AppDisplayName
alertDetailsOverride:
  alertDisplayNameFormat: "Off-Hours Privileged Sign-In — {{UserPrincipalName}} at {{HourOfDay}}:00 UTC from {{Location}}"
  alertDescriptionFormat: "Privileged account {{UserPrincipalName}} signed in at {{HourOfDay}}:00 UTC outside business hours. Investigate for unauthorized admin activity."
incidentConfiguration:
  createIncident: true
  groupingConfiguration:
    enabled: true
    reopenClosedIncident: false
    lookbackDuration: PT1H
    matchingMethod: AllEntities
    groupByEntities:
  - Account