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
Version	1.0.1
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

name: GSA - TI URL Entity
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:
- entityType: Account
  fieldMappings:
  - columnName: UserPrincipalName
    identifier: Name
- entityType: IP
  fieldMappings:
  - columnName: SourceIp
    identifier: Address
- entityType: URL
  fieldMappings:
  - columnName: DestinationUrl
    identifier: Url
- entityType: Process
  fieldMappings:
  - columnName: InitiatingProcessName
    identifier: CommandLine
queryPeriod: 14d
version: 1.0.1
tactics:
- CommandAndControl
triggerOperator: gt
kind: Scheduled
triggerThreshold: 0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Global Secure Access/Analytic Rules/GSA - TI URL Entity.yaml
relevantTechniques:
- T1071
id: 347c6cb3-33d2-4753-b7f6-eab946a8cd51
severity: Medium
requiredDataConnectors:
- connectorId: AzureActiveDirectory
  dataTypes:
  - NetworkAccessTrafficLogs
status: Available
description: |
    This query identifies URL indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in GSA NetworkAccessTraffic.
queryFrequency: 1h

ARM