TI Map URL Entity to Syslog Data

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Id	b31037ea-6f68-4fbd-bab2-d0d0f44c2fcf
Rulename	TI Map URL Entity to Syslog Data
Description	This query identifies any URL indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in Syslog data.
Severity	Medium
Tactics	CommandAndControl
Techniques	T1071
Required data connectors	MicrosoftDefenderThreatIntelligence Syslog ThreatIntelligence ThreatIntelligenceTaxii
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/Threat Intelligence/Analytic Rules/URLEntity_Syslog.yaml
Version	1.2.6
Arm template	b31037ea-6f68-4fbd-bab2-d0d0f44c2fcf.json

KQL

let dt_lookBack = 1h;
let ioc_lookBack = 14d;
ThreatIntelligenceIndicator
// Picking up only IOC's that contain the entities we want
| where isnotempty(Url)
| where TimeGenerated >= ago(ioc_lookBack)
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
| where Active == true and ExpirationDateTime > now()
// using innerunique to keep perf fast and result set low, we only need one match to indicate potential malicious activity that needs to be investigated
| join kind=innerunique (
  Syslog
  | where TimeGenerated >= ago(dt_lookBack)
  // Extract URL from the Syslog message but only take messages that include URLs
  | extend Url = extract("(http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\\(\\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+)", 1,SyslogMessage)
  | where isnotempty(Url)
  | extend Syslog_TimeGenerated = TimeGenerated
) on Url
| where Syslog_TimeGenerated < ExpirationDateTime
| summarize Syslog_TimeGenerated  = arg_max(Syslog_TimeGenerated , *) by IndicatorId, Url
| project timestamp = Syslog_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, ExpirationDateTime, ConfidenceScore, SyslogMessage, Computer, ProcessName, Url, HostIP

YAML

description: |
    'This query identifies any URL indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in Syslog data.'
version: 1.2.6
tactics:
- CommandAndControl
query: |
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  ThreatIntelligenceIndicator
  // Picking up only IOC's that contain the entities we want
  | where isnotempty(Url)
  | where TimeGenerated >= ago(ioc_lookBack)
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
  | where Active == true and ExpirationDateTime > now()
  // using innerunique to keep perf fast and result set low, we only need one match to indicate potential malicious activity that needs to be investigated
  | join kind=innerunique (
    Syslog
    | where TimeGenerated >= ago(dt_lookBack)
    // Extract URL from the Syslog message but only take messages that include URLs
    | extend Url = extract("(http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\\(\\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+)", 1,SyslogMessage)
    | where isnotempty(Url)
    | extend Syslog_TimeGenerated = TimeGenerated
  ) on Url
  | where Syslog_TimeGenerated < ExpirationDateTime
  | summarize Syslog_TimeGenerated  = arg_max(Syslog_TimeGenerated , *) by IndicatorId, Url
  | project timestamp = Syslog_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, ExpirationDateTime, ConfidenceScore, SyslogMessage, Computer, ProcessName, Url, HostIP  
triggerOperator: gt
kind: Scheduled
queryFrequency: 1h
triggerThreshold: 0
relevantTechniques:
- T1071
id: b31037ea-6f68-4fbd-bab2-d0d0f44c2fcf
queryPeriod: 14d
entityMappings:
- fieldMappings:
  - identifier: HostName
    columnName: Computer
  entityType: Host
- fieldMappings:
  - identifier: Address
    columnName: HostIP
  entityType: IP
- fieldMappings:
  - identifier: Url
    columnName: Url
  entityType: URL
severity: Medium
name: TI Map URL Entity to Syslog Data
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence/Analytic Rules/URLEntity_Syslog.yaml
requiredDataConnectors:
- dataTypes:
  - Syslog
  connectorId: Syslog
- dataTypes:
  - ThreatIntelligenceIndicator
  connectorId: ThreatIntelligence
- dataTypes:
  - ThreatIntelligenceIndicator
  connectorId: ThreatIntelligenceTaxii
- dataTypes:
  - ThreatIntelligenceIndicator
  connectorId: MicrosoftDefenderThreatIntelligence

ARM