Infoblox - TI - Syslog Match Found - URL

Status: available
Severity: medium
Time window: 14d
Group by: DomainName, IndicatorId, Url
Source: github.com/Azure/Azure-Sentinel

'Syslog URL match found in your Infoblox TIDE Threat Intelligence. Customize query count, scheduling, responses and more. Modify data sources, types and threat properties as desired.'

MITRE ATT&CK coverage

Tactic	Techniques
Impact	`T1498` Network Denial of Service `T1565` Data Manipulation

Rule body

id: 28ee3c2b-eb4b-44de-a71e-e462843fea72
name: Infoblox - TI - Syslog Match Found - URL
description: |
  'Syslog URL match found in your Infoblox TIDE Threat Intelligence. Customize query count, scheduling, responses and more. Modify data sources, types and threat properties as desired.'
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: Syslog
    dataTypes: 
      - Syslog
  - connectorId: ThreatIntelligence
    dataTypes: 
      - ThreatIntelligenceIndicator
  - connectorId: CefAma
    dataTypes:
      - CommonSecurityLog
queryFrequency: 1h
queryPeriod: 14d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Impact
relevantTechniques:
  - T1498
  - T1565
query: |
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  let TI = ThreatIntelligenceIndicator
  | where TimeGenerated >= ago(ioc_lookBack)
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
  | where Active == true and ExpirationDateTime > now()  
  | where Description has_cs "Infoblox - URL"
  | where isnotempty(DomainName)
  ;
  let Data = Syslog
  | extend HitTime = TimeGenerated
  | where TimeGenerated >= ago(dt_lookBack)
  //Extract URL patterns from syslog message
  | extend Url = extract("(http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\\(\\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+)", 1,SyslogMessage)
  | where isnotempty(Url)
  ;
  TI | join kind=innerunique Data on $left.DomainName == $right.Url
  | where HitTime >= TimeGenerated and HitTime < ExpirationDateTime
  | project LatestIndicatorTime, HitTime, SyslogMessage, Computer, ProcessName, Url, HostIP, 
  AdditionalInformation, Description, ThreatType, TrafficLightProtocolLevel, Type, ConfidenceScore, ExpirationDateTime, SourceSystem, Action, IndicatorId, ExternalIndicatorId, Tags
entityMappings:
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: HostIP
  - entityType: Host
    fieldMappings:
      - identifier: HostName
        columnName: Computer
  - entityType: DNS
    fieldMappings:
      - identifier: DomainName
        columnName: Url
  - entityType: URL
    fieldMappings:
      - identifier: Url
        columnName: Url
eventGroupingSettings:
  aggregationKind: SingleAlert
incidentConfiguration:
  createIncident: true
version: 1.0.3
kind: Scheduled

Stages and Predicates

Parameters

let dt_lookBack = 1h;
let ioc_lookBack = 14d;

let TI is inlined into the numbered stages below.

Let binding: `Data` used in Stage 7

let Data = Syslog
| extend HitTime = TimeGenerated
| where TimeGenerated >= ago(dt_lookBack)
| extend Url = extract("(http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\\(\\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+)", 1,SyslogMessage)
| where isnotempty(Url);

Stages 1 to 6 define let TI (the rule's main pipeline source); stages 7 to 9 run on it.

Stage 1: `source`

ThreatIntelligenceIndicator

Stage 2: `where`

| where TimeGenerated >= ago(ioc_lookBack)

Stage 3: `summarize`

| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId

Stage 4: `where`

| where Active == true and ExpirationDateTime > now()

Stage 5: `where`

| where Description has_cs "Infoblox - URL"

Stage 6: `where`

| where isnotempty(DomainName)

Stage 7: `join`

TI
| join kind=innerunique Data on $left.DomainName == $right.Url

Stage 8: `where`

| where HitTime >= TimeGenerated and HitTime < ExpirationDateTime

Stage 9: `project`

| project LatestIndicatorTime, HitTime, SyslogMessage, Computer, ProcessName, Url, HostIP, 
AdditionalInformation, Description, ThreatType, TrafficLightProtocolLevel, Type, ConfidenceScore, ExpirationDateTime, SourceSystem, Action, IndicatorId, ExternalIndicatorId, Tags

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`Active`	eq	`true`	`field:"Active" kind:eq value:"true"`
`Description`	match	`Infoblox - URL` transforms: `term`	`field:"Description" kind:match value:"Infoblox - URL"`
`DomainName`	is_not_null	(no value, null check)	`field:"DomainName" kind:is_not_null`
`HitTime`	cross_field_compare	`ExpirationDateTime` transforms: `op:lt` `TimeGenerated` transforms: `op:ge`	`field:"HitTime" kind:cross_field_compare`
`Url`	is_not_null	(no value, null check)	`field:"Url" kind:is_not_null`

Output fields

These fields are emitted when the rule matches.

Field	Source
`Action`	`project`
`AdditionalInformation`	`project`
`Computer`	`project`
`ConfidenceScore`	`project`
`Description`	`project`
`ExpirationDateTime`	`project`
`ExternalIndicatorId`	`project`
`HitTime`	`project`
`HostIP`	`project`
`IndicatorId`	`project`
`LatestIndicatorTime`	`project`
`ProcessName`	`project`
`SourceSystem`	`project`
`SyslogMessage`	`project`
`Tags`	`project`
`ThreatType`	`project`
`TrafficLightProtocolLevel`	`project`
`Type`	`project`
`Url`	`project`

Infoblox - TI - Syslog Match Found - URL

MITRE ATT&CK coverage

Rule body

Stages and Predicates

Parameters

Let binding: Data used in Stage 7

Stage 1: source

Stage 2: where

Stage 3: summarize

Stage 4: where

Stage 5: where

Stage 6: where

Stage 7: join

Stage 8: where

Stage 9: project