Attempt to bypass conditional access rule in Microsoft Entra ID

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Id	3af9285d-bb98-4a35-ad29-5ea39ba0c628
Rulename	Attempt to bypass conditional access rule in Microsoft Entra ID
Description	Identifies an attempt to Bypass conditional access rule(s) in Microsoft Entra ID. The ConditionalAccessStatus column value details if there was an attempt to bypass Conditional Access or if the Conditional access rule was not satisfied (ConditionalAccessStatus == 1). References: https://docs.microsoft.com/azure/active-directory/conditional-access/overview https://docs.microsoft.com/azure/active-directory/reports-monitoring/concept-sign-ins https://docs.microsoft.com/azure/active-directory/reports-monitoring/reference-sign-ins-error-codes ConditionalAccessStatus == 0 // Success ConditionalAccessStatus == 1 // Failure ConditionalAccessStatus == 2 // Not Applied ConditionalAccessStatus == 3 // unknown
Severity	Low
Tactics	InitialAccess Persistence
Techniques	T1078 T1098
Required data connectors	AzureActiveDirectory
Kind	Scheduled
Query frequency	1d
Query period	1d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/BypassCondAccessRule.yaml
Version	1.0.7
Arm template	3af9285d-bb98-4a35-ad29-5ea39ba0c628.json

KQL

let threshold = 1; // Modify this threshold value to reduce false positives based on your environment
let aadFunc = (tableName:string){
table(tableName)
| where ConditionalAccessStatus == 1 or ConditionalAccessStatus =~ "failure"
| mv-apply CAP = parse_json(ConditionalAccessPolicies) on (
  project ConditionalAccessPoliciesName = CAP.displayName, result = CAP.result
  | where result =~ "failure"
)
| extend DeviceDetail = todynamic(DeviceDetail), Status = todynamic(Status), LocationDetails = todynamic(LocationDetails)
| extend OS = DeviceDetail.operatingSystem, Browser = DeviceDetail.browser
| extend State = tostring(LocationDetails.state), City = tostring(LocationDetails.city), Region = tostring(LocationDetails.countryOrRegion)
| extend StatusCode = tostring(Status.errorCode), StatusDetails = tostring(Status.additionalDetails)
| extend Status = strcat(StatusCode, ": ", ResultDescription)
| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), Status = make_list(Status,10), StatusDetails = make_list(StatusDetails,50), IPAddresses = make_list(IPAddress,100), IPAddressCount = dcount(IPAddress), CorrelationIds = make_list(CorrelationId,100), ConditionalAccessPoliciesName = make_list(ConditionalAccessPoliciesName,100)
by UserPrincipalName, UserId, AppDisplayName, tostring(Browser), tostring(OS), City, State, Region, Type
| where IPAddressCount > threshold and StatusDetails !has "MFA successfully completed"
| mv-expand IPAddresses, Status, StatusDetails, CorrelationIds
| extend Status = strcat(Status, " ", StatusDetails)
| summarize IPAddresses = make_set(IPAddresses,100), Status = make_set(Status,10), CorrelationIds = make_set(CorrelationIds,100), ConditionalAccessPoliciesName = make_set(ConditionalAccessPoliciesName,100)
by StartTime, EndTime, UserPrincipalName, UserId, AppDisplayName, tostring(Browser), tostring(OS), City, State, Region, IPAddressCount, Type
| extend IPAddressFirst = tostring(IPAddresses[0]), Name = tostring(split(UserPrincipalName, "@")[0]), UPNSuffix = tostring(split(UserPrincipalName, "@")[1])
};
let aadSignin = aadFunc("SigninLogs");
let aadNonInt = aadFunc("AADNonInteractiveUserSignInLogs");
union isfuzzy=true aadSignin, aadNonInt

YAML

description: |
  'Identifies an attempt to Bypass conditional access rule(s) in Microsoft Entra ID.
  The ConditionalAccessStatus column value details if there was an attempt to bypass Conditional Access or if the Conditional access rule was not satisfied (ConditionalAccessStatus == 1).
  References:
  https://docs.microsoft.com/azure/active-directory/conditional-access/overview
  https://docs.microsoft.com/azure/active-directory/reports-monitoring/concept-sign-ins
  https://docs.microsoft.com/azure/active-directory/reports-monitoring/reference-sign-ins-error-codes
  ConditionalAccessStatus == 0 // Success
  ConditionalAccessStatus == 1 // Failure
  ConditionalAccessStatus == 2 // Not Applied
  ConditionalAccessStatus == 3 // unknown'  
kind: Scheduled
tactics:
- InitialAccess
- Persistence
requiredDataConnectors:
- connectorId: AzureActiveDirectory
  dataTypes:
  - SigninLogs
- connectorId: AzureActiveDirectory
  dataTypes:
  - AADNonInteractiveUserSignInLogs
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/BypassCondAccessRule.yaml
severity: Low
name: Attempt to bypass conditional access rule in Microsoft Entra ID
triggerThreshold: 0
queryPeriod: 1d
query: |
  let threshold = 1; // Modify this threshold value to reduce false positives based on your environment
  let aadFunc = (tableName:string){
  table(tableName)
  | where ConditionalAccessStatus == 1 or ConditionalAccessStatus =~ "failure"
  | mv-apply CAP = parse_json(ConditionalAccessPolicies) on (
    project ConditionalAccessPoliciesName = CAP.displayName, result = CAP.result
    | where result =~ "failure"
  )
  | extend DeviceDetail = todynamic(DeviceDetail), Status = todynamic(Status), LocationDetails = todynamic(LocationDetails)
  | extend OS = DeviceDetail.operatingSystem, Browser = DeviceDetail.browser
  | extend State = tostring(LocationDetails.state), City = tostring(LocationDetails.city), Region = tostring(LocationDetails.countryOrRegion)
  | extend StatusCode = tostring(Status.errorCode), StatusDetails = tostring(Status.additionalDetails)
  | extend Status = strcat(StatusCode, ": ", ResultDescription)
  | summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), Status = make_list(Status,10), StatusDetails = make_list(StatusDetails,50), IPAddresses = make_list(IPAddress,100), IPAddressCount = dcount(IPAddress), CorrelationIds = make_list(CorrelationId,100), ConditionalAccessPoliciesName = make_list(ConditionalAccessPoliciesName,100)
  by UserPrincipalName, UserId, AppDisplayName, tostring(Browser), tostring(OS), City, State, Region, Type
  | where IPAddressCount > threshold and StatusDetails !has "MFA successfully completed"
  | mv-expand IPAddresses, Status, StatusDetails, CorrelationIds
  | extend Status = strcat(Status, " ", StatusDetails)
  | summarize IPAddresses = make_set(IPAddresses,100), Status = make_set(Status,10), CorrelationIds = make_set(CorrelationIds,100), ConditionalAccessPoliciesName = make_set(ConditionalAccessPoliciesName,100)
  by StartTime, EndTime, UserPrincipalName, UserId, AppDisplayName, tostring(Browser), tostring(OS), City, State, Region, IPAddressCount, Type
  | extend IPAddressFirst = tostring(IPAddresses[0]), Name = tostring(split(UserPrincipalName, "@")[0]), UPNSuffix = tostring(split(UserPrincipalName, "@")[1])
  };
  let aadSignin = aadFunc("SigninLogs");
  let aadNonInt = aadFunc("AADNonInteractiveUserSignInLogs");
  union isfuzzy=true aadSignin, aadNonInt  
relevantTechniques:
- T1078
- T1098
id: 3af9285d-bb98-4a35-ad29-5ea39ba0c628
queryFrequency: 1d
status: Available
triggerOperator: gt
version: 1.0.7
entityMappings:
- entityType: Account
  fieldMappings:
  - columnName: UserPrincipalName
    identifier: FullName
  - columnName: Name
    identifier: Name
  - columnName: UPNSuffix
    identifier: UPNSuffix
- entityType: Account
  fieldMappings:
  - columnName: UserId
    identifier: AadUserId
- entityType: IP
  fieldMappings:
  - columnName: IPAddressFirst
    identifier: Address

ARM