[Deprecated] Explicit MFA Deny

Back


Id	a22740ec-fc1e-4c91-8de6-c29c6450ad00
Rulename	[Deprecated] Explicit MFA Deny
Description	User explicitly denies MFA push, indicating that login was not expected and the account’s password may be compromised. This rule is deprecated as of July-2024. Alternative rule with similar logic and contex from more data source is available at https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft%20Entra%20ID/Analytic%20Rules/MFARejectedbyUser.yaml
Severity	Medium
Tactics	CredentialAccess
Techniques	T1110
Required data connectors	AzureActiveDirectory MicrosoftThreatProtection
Kind	Scheduled
Query frequency	1h
Query period	1h
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/ExplicitMFADeny.yaml
Version	1.0.7
Arm template	a22740ec-fc1e-4c91-8de6-c29c6450ad00.json

KQL

let aadFunc = (tableName: string) {
    table(tableName)
    | where ResultType == 500121
    | where Status has "MFA Denied; user declined the authentication" or Status has "MFA denied; Phone App Reported Fraud"
    | extend Type = Type, PublicIP = IPAddress
    | extend
        Name = tostring(split(UserPrincipalName, '@', 0)[0]),
        UPNSuffix = tostring(split(UserPrincipalName, '@', 1)[0])
};
let aadSignin = aadFunc("SigninLogs");
let dvcInfo = DeviceInfo
    | extend SensorHealthState = column_ifexists("SensorHealthState", "")
    | where OnboardingStatus == "Onboarded" and SensorHealthState == "Active"
    | project PublicIP, AadDeviceId;
let aadNonInt = aadFunc("AADNonInteractiveUserSignInLogs");
union isfuzzy=true aadSignin, aadNonInt
| join kind=leftouter dvcInfo on PublicIP

YAML

description: |
  'User explicitly denies MFA push, indicating that login was not expected and the account's password may be compromised.
  This rule is deprecated as of July-2024. Alternative rule with similar logic and contex from more data source 
  is available at https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft%20Entra%20ID/Analytic%20Rules/MFARejectedbyUser.yaml'  
kind: Scheduled
tactics:
- CredentialAccess
requiredDataConnectors:
- connectorId: AzureActiveDirectory
  dataTypes:
  - SigninLogs
- connectorId: AzureActiveDirectory
  dataTypes:
  - AADNonInteractiveUserSignInLogs
- connectorId: MicrosoftThreatProtection
  dataTypes:
  - DeviceInfo
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/ExplicitMFADeny.yaml
severity: Medium
name: '[Deprecated] Explicit MFA Deny'
triggerThreshold: 0
queryPeriod: 1h
query: |
  let aadFunc = (tableName: string) {
      table(tableName)
      | where ResultType == 500121
      | where Status has "MFA Denied; user declined the authentication" or Status has "MFA denied; Phone App Reported Fraud"
      | extend Type = Type, PublicIP = IPAddress
      | extend
          Name = tostring(split(UserPrincipalName, '@', 0)[0]),
          UPNSuffix = tostring(split(UserPrincipalName, '@', 1)[0])
  };
  let aadSignin = aadFunc("SigninLogs");
  let dvcInfo = DeviceInfo
      | extend SensorHealthState = column_ifexists("SensorHealthState", "")
      | where OnboardingStatus == "Onboarded" and SensorHealthState == "Active"
      | project PublicIP, AadDeviceId;
  let aadNonInt = aadFunc("AADNonInteractiveUserSignInLogs");
  union isfuzzy=true aadSignin, aadNonInt
  | join kind=leftouter dvcInfo on PublicIP  
relevantTechniques:
- T1110
id: a22740ec-fc1e-4c91-8de6-c29c6450ad00
queryFrequency: 1h
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: IP
  fieldMappings:
  - columnName: PublicIP
    identifier: Address
- entityType: AzureResource
  fieldMappings:
  - columnName: ResourceId
    identifier: ResourceId
- entityType: CloudApplication
  fieldMappings:
  - columnName: AppDisplayName
    identifier: Name
  - columnName: AppId
    identifier: AppId

ARM