Detection rules › Kusto
GreyNoise TI Map IP Entity to SigninLogs
This query maps any GreyNoise IP indicators of compromise (IOCs) from threat intelligence (TI), by searching for matches in SigninLogs.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Command & Control |
Telemetry coverage
Rule body
id: f6c76cc9-218c-5b76-9b82-8607f09ea1b4
name: GreyNoise TI Map IP Entity to SigninLogs
version: 1.0.1
kind: Scheduled
description: |
'This query maps any GreyNoise IP indicators of compromise (IOCs) from threat intelligence (TI), by searching for matches in SigninLogs.'
severity: Medium
requiredDataConnectors:
- connectorId: ThreatIntelligence
dataTypes:
- ThreatIntelligenceIndicator
- connectorId: ThreatIntelligenceTaxii
dataTypes:
- ThreatIntelligenceIndicator
- connectorId: AzureActiveDirectory
dataTypes:
- SigninLogs
- connectorId: AzureActiveDirectory
dataTypes:
- AADNonInteractiveUserSignInLogs
- connectorId: MicrosoftDefenderThreatIntelligence
dataTypes:
- ThreatIntelligenceIndicator
- connectorId: GreyNoise2SentinelAPI
dataTypes:
- ThreatIntelligenceIndicator
queryFrequency: 1h
queryPeriod: 14d
triggerOperator: gt
triggerThreshold: 0
tactics:
- CommandAndControl
relevantTechniques:
- T1071
query: |
let dt_lookBack = 1h;
let ioc_lookBack = 14d;
let aadFunc = (tableName:string){
ThreatIntelligenceIndicator
| where TimeGenerated >= ago(ioc_lookBack)
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
| where Active == true and ExpirationDateTime > now()
| where SourceSystem == 'GreyNoise'
// Picking up only IOC's that contain the entities we want
| where isnotempty(NetworkIP) or isnotempty(EmailSourceIpAddress) or isnotempty(NetworkDestinationIP) or isnotempty(NetworkSourceIP)
// As there is potentially more than 1 indicator type for matching IP, taking NetworkIP first, then others if that is empty.
// Taking the first non-empty value based on potential IOC match availability
| extend TI_ipEntity = iff(isnotempty(NetworkIP), NetworkIP, NetworkDestinationIP)
| extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)
| extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(EmailSourceIpAddress), EmailSourceIpAddress, TI_ipEntity)
// 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 (
table(tableName) | where TimeGenerated >= ago(dt_lookBack)
| extend Status = todynamic(Status), LocationDetails = todynamic(LocationDetails)
| extend StatusCode = tostring(Status.errorCode), StatusDetails = tostring(Status.additionalDetails), StatusReason = tostring(Status.failureReason)
| extend State = tostring(LocationDetails.state), City = tostring(LocationDetails.city), Region = tostring(LocationDetails.countryOrRegion)
// renaming time column so it is clear the log this came from
| extend SigninLogs_TimeGenerated = TimeGenerated, Type = Type
)
on $left.TI_ipEntity == $right.IPAddress
| where SigninLogs_TimeGenerated < ExpirationDateTime
| summarize SigninLogs_TimeGenerated = arg_max(SigninLogs_TimeGenerated, *) by IndicatorId, IPAddress
| project SigninLogs_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, ExpirationDateTime, ConfidenceScore,
TI_ipEntity, IPAddress, UserPrincipalName, AppDisplayName, StatusCode, StatusDetails, StatusReason, NetworkIP, NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress, Type
| extend timestamp = SigninLogs_TimeGenerated, Name = tostring(split(UserPrincipalName, '@', 0)[0]), UPNSuffix = tostring(split(UserPrincipalName, '@', 1)[0])
};
let aadSignin = aadFunc("SigninLogs");
let aadNonInt = aadFunc("AADNonInteractiveUserSignInLogs");
union isfuzzy=true aadSignin, aadNonInt
entityMappings:
- entityType: Account
fieldMappings:
- identifier: Name
columnName: Name
- identifier: UPNSuffix
columnName: UPNSuffix
- entityType: IP
fieldMappings:
- identifier: Address
columnName: IPAddress
- entityType: URL
fieldMappings:
- identifier: Url
columnName: Url
Stages and Predicates
Parameters
let dt_lookBack = 1h;
let ioc_lookBack = 14d;
let aadSignin = aadFunc("SigninLogs");
let aadNonInt = aadFunc("AADNonInteractiveUserSignInLogs");
Let binding: aadFunc
let aadFunc = (tableName:string){
ThreatIntelligenceIndicator
| where TimeGenerated >= ago(ioc_lookBack)
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
| where Active == true and ExpirationDateTime > now()
| where SourceSystem == 'GreyNoise'
| where isnotempty(NetworkIP) or isnotempty(EmailSourceIpAddress) or isnotempty(NetworkDestinationIP) or isnotempty(NetworkSourceIP)
| extend TI_ipEntity = iff(isnotempty(NetworkIP), NetworkIP, NetworkDestinationIP)
| extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)
| extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(EmailSourceIpAddress), EmailSourceIpAddress, TI_ipEntity)
| join kind=innerunique (
table(tableName) | where TimeGenerated >= ago(dt_lookBack)
| extend Status = todynamic(Status), LocationDetails = todynamic(LocationDetails)
| extend StatusCode = tostring(Status.errorCode), StatusDetails = tostring(Status.additionalDetails), StatusReason = tostring(Status.failureReason)
| extend State = tostring(LocationDetails.state), City = tostring(LocationDetails.city), Region = tostring(LocationDetails.countryOrRegion)
| extend SigninLogs_TimeGenerated = TimeGenerated, Type = Type
)
on $left.TI_ipEntity == $right.IPAddress
| where SigninLogs_TimeGenerated < ExpirationDateTime
| summarize SigninLogs_TimeGenerated = arg_max(SigninLogs_TimeGenerated, *) by IndicatorId, IPAddress
| project SigninLogs_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, ExpirationDateTime, ConfidenceScore,
TI_ipEntity, IPAddress, UserPrincipalName, AppDisplayName, StatusCode, StatusDetails, StatusReason, NetworkIP, NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress, Type
| extend timestamp = SigninLogs_TimeGenerated, Name = tostring(split(UserPrincipalName, '@', 0)[0]), UPNSuffix = tostring(split(UserPrincipalName, '@', 1)[0])
};
union isfuzzy=true (2 sources)
Each leg below queries one source; the rule matches if any leg does. Sources: aadSignin, aadNonInt
Leg 1: aadSignin
Leg 2: aadNonInt
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
Active | eq |
| field:"Active" kind:eq value:"true" |
EmailSourceIpAddress | is_not_null | field:"EmailSourceIpAddress" kind:is_not_null | |
NetworkDestinationIP | is_not_null | field:"NetworkDestinationIP" kind:is_not_null | |
NetworkIP | is_not_null | field:"NetworkIP" kind:is_not_null | |
NetworkSourceIP | is_not_null | field:"NetworkSourceIP" kind:is_not_null | |
SigninLogs_TimeGenerated | cross_field_compare |
| field:"SigninLogs_TimeGenerated" kind:cross_field_compare value:"ExpirationDateTime" |
SourceSystem | eq |
| field:"SourceSystem" kind:eq value:"GreyNoise" |
Output fields
These fields are emitted when the rule matches.
| Field | Source |
|---|---|
ActivityGroupNames | project |
AppDisplayName | project |
ConfidenceScore | project |
Description | project |
EmailSourceIpAddress | project |
ExpirationDateTime | project |
IPAddress | project |
IndicatorId | project |
NetworkDestinationIP | project |
NetworkIP | project |
NetworkSourceIP | project |
SigninLogs_TimeGenerated | project |
StatusCode | project |
StatusDetails | project |
StatusReason | project |
TI_ipEntity | project |
ThreatType | project |
Type | project |
Url | project |
UserPrincipalName | project |
Name | extend |
UPNSuffix | extend |
timestamp | extend |