Query Details
id: bd676415-d309-41e0-87f7-4a9e52d81c14
name: AzureHound reconnaissance detected
version: 1.0.0
kind: Scheduled
description: Microsoft Graph queries that are similar to AzureHound where detected in your environment. An attacker might have started with the reconnaissance stage of an attack in your environment. This requires access to a compromised identity.
severity: Medium
queryFrequency: 30m
queryPeriod: 40m
triggerOperator: gt
triggerThreshold: 0
tactics:
- Reconnaissance
- InitialAccess
relevantTechniques:
- T1595
- T1589
- T1591
- T1078
query: |-
let AzureHoundGraphQueries = dynamic([
"https:/graph.microsoft.com/version/servicePrincipals/<UUID>/owners",
"https:/graph.microsoft.com/version/groups/<UUID>/members",
"https:/graph.microsoft.com/version/groups/<UUID>/owners",
"https:/graph.microsoft.com/version/servicePrincipals/<UUID>/appRoleAssignedTo",
"https:/graph.microsoft.com/version/roleManagement/directory/roleAssignments",
"https:/graph.microsoft.com/version/applications/<UUID>/owners",
"https:/graph.microsoft.com/version/devices/<UUID>/registeredOwners",
"https:/graph.microsoft.com/version/organization",
"https:/graph.microsoft.com/version/groups",
"https:/graph.microsoft.com/version/servicePrincipals",
"https:/graph.microsoft.com/version/applications",
"https:/graph.microsoft.com/version/roleManagement/directory/roleDefinitions",
"https:/graph.microsoft.com/version/devices",
"https:/graph.microsoft.com/version/users"
]);
let PotentialMaliciousGraphCalls = materialize (
MicrosoftGraphActivityLogs
| where ingestion_time() > ago(35m)
| extend ObjectId = iff(isempty(UserId), ServicePrincipalId, UserId)
| extend ObjectType = iff(isempty(UserId), "ServicePrincipalId", "UserId")
| where RequestUri !has "microsoft.graph.delta"
| extend NormalizedRequestUri = replace_regex(RequestUri, @'[0-9a-fA-F]{8}\b-[0-9a-fA-F]{4}\b-[0-9a-fA-F]{4}\b-[0-9a-fA-F]{4}\b-[0-9a-fA-F]{12}', @'<UUID>')
| extend NormalizedRequestUri = replace_regex(NormalizedRequestUri, @'\d+$', @'<UUID>')
| extend NormalizedRequestUri = replace_regex(NormalizedRequestUri, @'\/+', @'/')
| extend NormalizedRequestUri = replace_regex(NormalizedRequestUri, @'\/(v1\.0|beta)\/', @'/version/')
| extend NormalizedRequestUri = replace_regex(NormalizedRequestUri, @'%23EXT%23', @'')
| extend NormalizedRequestUri = replace_regex(NormalizedRequestUri, @'\/[a-zA-Z0-9+_.\-]+@[a-zA-Z0-9.]+\/', @'/<UUID>/')
| extend NormalizedRequestUri = replace_regex(NormalizedRequestUri, @'^\/<UUID>', @'')
| extend NormalizedRequestUri = replace_regex(NormalizedRequestUri, @'\?.*$', @'')
| summarize
GraphEndpointsCalled = make_set(NormalizedRequestUri, 1000),
IPAddresses = make_set(IpAddress)
by ObjectId, ObjectType
| project
ObjectId,
ObjectType,
IPAddresses,
MatchingQueries=set_intersect(AzureHoundGraphQueries, GraphEndpointsCalled)
| extend ConfidenceScore = round(todouble(array_length(MatchingQueries)) / todouble(array_length(AzureHoundGraphQueries)), 1)
| where ConfidenceScore > 0.7);
let IPEntities = PotentialMaliciousGraphCalls
| mv-expand IPAddresses
| sort by ObjectId
| extend CurrentRowNumber=row_number(2, prev(ObjectId) != ObjectId)
| extend IPInformation = bag_pack(@"$id", CurrentRowNumber, "Address", IPAddresses, "Type", "ip")
| project ObjectId, IPInformation
| summarize IPInformation = make_set(IPInformation, 150) by ObjectId;
PotentialMaliciousGraphCalls
| join kind=leftouter IPEntities on ObjectId
| project-away IPAddresses, *1, *2
suppressionEnabled: false
incidentConfiguration:
createIncident: true
groupingConfiguration:
enabled: false
reopenClosedIncident: false
lookbackDuration: 5h
matchingMethod: AllEntities
groupByEntities: []
groupByAlertDetails: []
groupByCustomDetails: []
eventGroupingSettings:
aggregationKind: AlertPerResult
alertDetailsOverride:
alertDynamicProperties:
- alertProperty: ConfidenceScore
value: ConfidenceScore
entityMappings:
- entityType: Account
fieldMappings:
- identifier: AadUserId
columnName: ObjectId
sentinelEntitiesMappings:
- columnName: IPInformation
suppressionDuration: 5h
The query is designed to detect potential malicious activity in your environment related to Microsoft Graph queries similar to AzureHound. It looks for specific URLs in the Microsoft Graph API and matches them with activity logs. It calculates a confidence score based on the number of matching queries and compares it to a threshold. If the score is above the threshold, it identifies the potential malicious calls and extracts IP addresses associated with them. The query also includes incident configuration settings and entity mappings for further analysis.

Fabian Bader
Released: October 14, 2023
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