Detection rules › Kusto
Cross-Cloud Password Spray detection
'This detection focuses on identifying potential cross-cloud brute force / Password Spray attempts involving Azure and AWS platforms. It monitors sign-in activities within the Azure Portal and AWS ConsoleLogins where brute force attempts are successful on both platforms in a synchronized manner.'
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Credential Access | T1110 Brute Force |
Rules detecting the same action
Other rules on this platform that filter on the same API call or operation.
- AWS Console Login (Panther)
- AWS Console Login Failed During MFA Challenge (Splunk)
- AWS ConsoleLogin Failed Authentication (Sigma)
- AWS CreateLoginProfile (Splunk)
- AWS Credential Access Failed Login (Splunk)
- AWS High Number Of Failed Authentications For User (Splunk)
- AWS High Number Of Failed Authentications From Ip (Splunk)
- AWS Multiple Failed MFA Requests For User (Splunk)
Rule body kusto
id: 1f40ed57-f54b-462f-906a-ac3a89cc90d4
name: Cross-Cloud Password Spray detection
description: |
'This detection focuses on identifying potential cross-cloud brute force / Password Spray attempts involving Azure and AWS platforms. It monitors sign-in activities within the Azure Portal and AWS ConsoleLogins where brute force attempts are successful on both platforms in a synchronized manner.'
severity: Medium
requiredDataConnectors:
- connectorId: AWS
dataTypes:
- AWSCloudTrail
- connectorId: AzureActiveDirectory
dataTypes:
- SigninLogs
- connectorId: BehaviorAnalytics
dataTypes:
- IdentityInfo
- connectorId: MicrosoftThreatProtection
dataTypes:
- SecurityAlert
queryFrequency: 1d
queryPeriod: 1d
triggerOperator: gt
triggerThreshold: 0
tactics:
- CredentialAccess
relevantTechniques:
- T1110
query: |
// Materialize a table named "Azure_Bruforce" containing Azure Portal sign-in logs within the last 1 day
let Azure_Bruforce = materialize (
SigninLogs
// Filter sign-in logs related to the Azure Portal
| where AppDisplayName == "Azure Portal"
// Exclude entries with empty OriginalRequestId
| where isnotempty(OriginalRequestId)
// Summarize various counts and sets based on brute force criteria
| summarize
AzureSuccessfulEvent = countif(ResultType == 0),
AzureFailedEvent = countif(ResultType != 0),
totalAzureLoginEventId = dcount(OriginalRequestId),
AzureFailedEventsCount = dcountif(OriginalRequestId, ResultType != 0),
AzureSuccessfuleventsCount = dcountif(OriginalRequestId, ResultType == 0),
AzureSetOfFailedevents = makeset(iff(ResultType != 0, OriginalRequestId, ""), 5),
AzureSetOfSuccessfulEvents = makeset(iff(ResultType == 0, OriginalRequestId, ""), 5)
by
IPAddress,
UserPrincipalName,
bin(TimeGenerated, 1min),
UserAgent,
ConditionalAccessStatus,
OperationName,
RiskDetail,
AuthenticationRequirement,
ClientAppUsed
// Extracting the name and UPN suffix from UserPrincipalName
| extend
Name = tostring(split(UserPrincipalName, '@')[0]),
UPNSuffix = tostring(split(UserPrincipalName, '@')[1]));
// Materialize a table named "AWS_Bruforce" containing AWS CloudTrail events related to ConsoleLogins within the last 1 day
let AWS_Bruforce = materialize (
AWSCloudTrail
// Filter CloudTrail events related to ConsoleLogin
| where EventName == "ConsoleLogin"
// Extract ActionType from ResponseElements JSON
| extend ActionType = tostring(parse_json(ResponseElements).ConsoleLogin)
// Summarize various counts and sets based on brute force criteria
| summarize
AWSSuccessful=countif(ActionType == "Success"),
AWSFailed = countif(ActionType == "Failure"),
totalAwsEventId= dcount(AwsEventId),
AWSFailedEventsCount = dcountif(AwsEventId, ActionType == "Failure"),
AWSSuccessfuleventsCount = dcountif(AwsEventId, ActionType == "Success"),
AWSFailedevents = makeset(iff(ActionType == "Failure", AwsEventId, ""), 5),
AWSSuccessfulEvents = makeset(iff(ActionType == "Success", AwsEventId, ""), 5)
// Grouping by various attributes
by
SourceIpAddress,
UserIdentityUserName,
bin(TimeGenerated, 1min),
UserAgent );
// Joining the Azure_Bruforce and AWS_Bruforce tables on matching IP addresses and UserAgents
Azure_Bruforce
| join kind=inner AWS_Bruforce on $left.IPAddress == $right.SourceIpAddress and $left.UserAgent == $right.UserAgent
// Filtering based on conditions for failed and successful events
| where (AWSFailedEventsCount >= 4 and AzureFailedEventsCount >= 5) and ((AzureSuccessfuleventsCount >= 1 and AzureFailedEvent > AzureSuccessfulEvent) or (AWSSuccessfuleventsCount >= 1 and AWSFailedEventsCount > AWSSuccessfuleventsCount))
entityMappings:
- entityType: Account
fieldMappings:
- identifier: FullName
columnName: UserPrincipalName
- identifier: Name
columnName: Name
- identifier: UPNSuffix
columnName: UPNSuffix
- entityType: IP
fieldMappings:
- identifier: Address
columnName: SourceIpAddress
customDetails:
AwsUser: UserIdentityUserName
UserAgent: UserAgent
AzureUser: UserPrincipalName
AzureClientAppUsed: ClientAppUsed
kind: Scheduled
version: 1.0.1
Stages and Predicates
Let binding: AWS_Bruforce
let AWS_Bruforce = materialize (
AWSCloudTrail
| where EventName == "ConsoleLogin"
| extend ActionType = tostring(parse_json(ResponseElements).ConsoleLogin)
| summarize
AWSSuccessful=countif(ActionType == "Success"),
AWSFailed = countif(ActionType == "Failure"),
totalAwsEventId= dcount(AwsEventId),
AWSFailedEventsCount = dcountif(AwsEventId, ActionType == "Failure"),
AWSSuccessfuleventsCount = dcountif(AwsEventId, ActionType == "Success"),
AWSFailedevents = makeset(iff(ActionType == "Failure", AwsEventId, ""), 5),
AWSSuccessfulEvents = makeset(iff(ActionType == "Success", AwsEventId, ""), 5)
by
SourceIpAddress,
UserIdentityUserName,
bin(TimeGenerated, 1min),
UserAgent );
The stages below define let Azure_Bruforce (the rule's main pipeline source).
Stage 1: source
SigninLogs
Stage 2: where
| where AppDisplayName == "Azure Portal"
Stage 3: where
| where isnotempty(OriginalRequestId)
Stage 4: summarize
| summarize
AzureSuccessfulEvent = countif(ResultType == 0),
AzureFailedEvent = countif(ResultType != 0),
totalAzureLoginEventId = dcount(OriginalRequestId),
AzureFailedEventsCount = dcountif(OriginalRequestId, ResultType != 0),
AzureSuccessfuleventsCount = dcountif(OriginalRequestId, ResultType == 0),
AzureSetOfFailedevents = makeset(iff(ResultType != 0, OriginalRequestId, ""), 5),
AzureSetOfSuccessfulEvents = makeset(iff(ResultType == 0, OriginalRequestId, ""), 5)
by
IPAddress,
UserPrincipalName,
bin(TimeGenerated, 1min),
UserAgent,
ConditionalAccessStatus,
OperationName,
RiskDetail,
AuthenticationRequirement,
ClientAppUsed
Stage 5: extend
| extend
Name = tostring(split(UserPrincipalName, '@')[0]),
UPNSuffix = tostring(split(UserPrincipalName, '@')[1])
The stages below run on Azure_Bruforce (the outer pipeline).
Stage 6: join
Azure_Bruforce
| join kind=inner AWS_Bruforce on $left.IPAddress == $right.SourceIpAddress and $left.UserAgent == $right.UserAgent
Stage 7: where
| where (AWSFailedEventsCount >= 4 and AzureFailedEventsCount >= 5) and ((AzureSuccessfuleventsCount >= 1 and AzureFailedEvent > AzureSuccessfulEvent) or (AWSSuccessfuleventsCount >= 1 and AWSFailedEventsCount > AWSSuccessfuleventsCount))
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
AWSFailedEventsCount | ge |
|
AWSFailedEventsCount | gt |
|
AWSSuccessfuleventsCount | ge |
|
AppDisplayName | eq |
|
AzureFailedEvent | gt |
|
AzureFailedEventsCount | ge |
|
AzureSuccessfuleventsCount | ge |
|
EventName | eq |
|
OriginalRequestId | is_not_null |
Output fields
Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.
| Field | Source |
|---|---|
AuthenticationRequirement | summarize |
AzureFailedEvent | summarize |
AzureFailedEventsCount | summarize |
AzureSetOfFailedevents | summarize |
AzureSetOfSuccessfulEvents | summarize |
AzureSuccessfulEvent | summarize |
AzureSuccessfuleventsCount | summarize |
ClientAppUsed | summarize |
ConditionalAccessStatus | summarize |
IPAddress | summarize |
OperationName | summarize |
RiskDetail | summarize |
UserAgent | summarize |
UserPrincipalName | summarize |
totalAzureLoginEventId | summarize |
Name | extend |
UPNSuffix | extend |