GSA - TI URL Entity

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Id	347c6cb3-33d2-4753-b7f6-eab946a8cd51
Rulename	GSA - TI URL Entity
Description	This query identifies URL indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in GSA NetworkAccessTraffic.
Severity	Medium
Tactics	CommandAndControl
Techniques	T1071
Required data connectors	AzureActiveDirectory
Kind	Scheduled
Query frequency	1h
Query period	14d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Global Secure Access/Analytic Rules/GSA - TI URL Entity.yaml
Arm template	347c6cb3-33d2-4753-b7f6-eab946a8cd51.json

KQL

let dt_lookBack = 1h;
let ioc_lookBack = 14d;
let GSANetworkAccessTraffic_ = NetworkAccessTraffic
| where TimeGenerated >= ago(dt_lookBack)
| where TrafficType  == "internet"
| extend DestinationUrlToLower = tolower(DestinationUrl)
| project-rename GSANetworkAccessTraffic_TimeGenerated = TimeGenerated;
let GSANetworkAccessTrafficUrls =
    GSANetworkAccessTraffic_
    | where isnotempty(DestinationUrl)
    | extend Url = tolower(DestinationUrl)
    | distinct Url;
ThreatIntelIndicators
  | extend IndicatorType = replace(@'\[|\]|"""', "", tostring(split(ObservableKey, ":", 0)))
  | where IndicatorType == "url"
  | extend Url = ObservableValue
  | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
  | where TimeGenerated >= ago(ioc_lookBack)
  | extend Url = tolower(Url)
  | where Url in (GSANetworkAccessTrafficUrls)
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
  | where IsActive and (ValidUntil > now() or isempty(ValidUntil))
  | extend Description = tostring(parse_json(Data).description)
  | where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;"
  | project-reorder *, Tags, TrafficLightProtocolLevel, Url, Type
  | join kind=innerunique (GSANetworkAccessTraffic_) on $left.Url == $right.DestinationUrlToLower
  | where isempty(ValidUntil) or GSANetworkAccessTraffic_TimeGenerated < ValidUntil
  | extend GSAThreatType = ThreatType
| summarize GSANetworkAccessTraffic_TimeGenerated = arg_max(GSANetworkAccessTraffic_TimeGenerated, *) by Id, DestinationUrl
| project-reorder *,
    Tags,
    Confidence,
    TrafficLightProtocolLevel,
    Type,
    UserPrincipalName,
    UserId,
    DeviceId,
    InitiatingProcessName,
    GSAThreatType,
    DestinationIp,
    DestinationFqdn,
    DestinationUrl,
    DestinationPort,
    SourceIp,
    SourcePort,
    HttpUserAgent

YAML

kind: Scheduled
queryFrequency: 1h
queryPeriod: 14d
status: Available
tactics:
- CommandAndControl
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Global Secure Access/Analytic Rules/GSA - TI URL Entity.yaml
triggerThreshold: 0
description: |
    This query identifies URL indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in GSA NetworkAccessTraffic.
severity: Medium
relevantTechniques:
- T1071
id: 347c6cb3-33d2-4753-b7f6-eab946a8cd51
name: GSA - TI URL Entity
requiredDataConnectors:
- dataTypes:
  - NetworkAccessTrafficLogs
  connectorId: AzureActiveDirectory
query: |
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  let GSANetworkAccessTraffic_ = NetworkAccessTraffic
  | where TimeGenerated >= ago(dt_lookBack)
  | where TrafficType  == "internet"
  | extend DestinationUrlToLower = tolower(DestinationUrl)
  | project-rename GSANetworkAccessTraffic_TimeGenerated = TimeGenerated;
  let GSANetworkAccessTrafficUrls =
      GSANetworkAccessTraffic_
      | where isnotempty(DestinationUrl)
      | extend Url = tolower(DestinationUrl)
      | distinct Url;
  ThreatIntelIndicators
    | extend IndicatorType = replace(@'\[|\]|"""', "", tostring(split(ObservableKey, ":", 0)))
    | where IndicatorType == "url"
    | extend Url = ObservableValue
    | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
    | where TimeGenerated >= ago(ioc_lookBack)
    | extend Url = tolower(Url)
    | where Url in (GSANetworkAccessTrafficUrls)
    | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
    | where IsActive and (ValidUntil > now() or isempty(ValidUntil))
    | extend Description = tostring(parse_json(Data).description)
    | where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;"
    | project-reorder *, Tags, TrafficLightProtocolLevel, Url, Type
    | join kind=innerunique (GSANetworkAccessTraffic_) on $left.Url == $right.DestinationUrlToLower
    | where isempty(ValidUntil) or GSANetworkAccessTraffic_TimeGenerated < ValidUntil
    | extend GSAThreatType = ThreatType
  | summarize GSANetworkAccessTraffic_TimeGenerated = arg_max(GSANetworkAccessTraffic_TimeGenerated, *) by Id, DestinationUrl
  | project-reorder *,
      Tags,
      Confidence,
      TrafficLightProtocolLevel,
      Type,
      UserPrincipalName,
      UserId,
      DeviceId,
      InitiatingProcessName,
      GSAThreatType,
      DestinationIp,
      DestinationFqdn,
      DestinationUrl,
      DestinationPort,
      SourceIp,
      SourcePort,
      HttpUserAgent  
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: UserPrincipalName
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: SourceIp
  entityType: IP
- fieldMappings:
  - identifier: Url
    columnName: DestinationUrl
  entityType: URL
- fieldMappings:
  - identifier: CommandLine
    columnName: InitiatingProcessName
  entityType: Process
triggerOperator: gt

ARM