Multi-Factor Authentication Disabled for a User

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Id	65c78944-930b-4cae-bd79-c3664ae30ba7
Rulename	Multi-Factor Authentication Disabled for a User
Description	Multi-Factor Authentication (MFA) helps prevent credential compromise. This alert identifies when an attempt has been made to deactivate MFA for a user.
Severity	Medium
Tactics	CredentialAccess Persistence
Techniques	T1098 T1556
Required data connectors	AWS AzureActiveDirectory
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/Cloud Identity Threat Protection Essentials/Analytic Rules/MFADisable.yaml
Version	1.0.5
Arm template	65c78944-930b-4cae-bd79-c3664ae30ba7.json

KQL

(union isfuzzy=true
(AuditLogs
| where OperationName =~ "Disable Strong Authentication"
| extend _parsedIntiatedByUser = parse_json(tostring(InitiatedBy.user))
| extend _parsedIntiatedByApp = parse_json(tostring(InitiatedBy.app))
| extend IPAddress = tostring(_parsedIntiatedByUser.ipAddress)
| extend InitiatedByUser = iff(isnotempty(tostring(_parsedIntiatedByUser.userPrincipalName)),
 tostring(_parsedIntiatedByUser.userPrincipalName), tostring(_parsedIntiatedByApp.displayName))
| extend Targetprop = todynamic(TargetResources)
| extend TargetUser = tostring(Targetprop[0].userPrincipalName)
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated) by User = TargetUser, InitiatedByUser , Operation = OperationName , CorrelationId, IPAddress, Category, Source = SourceSystem , AADTenantId, Type
),
(AWSCloudTrail
| where EventName in~ ("DeactivateMFADevice", "DeleteVirtualMFADevice")
| extend _parsedRequestParameters = parse_json(RequestParameters)
| extend InstanceProfileName = tostring(_parsedRequestParameters.InstanceProfileName)
| extend TargetUser = tostring(_parsedRequestParameters.userName)
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated) by User = TargetUser, Source = EventSource , Operation = EventName , TenantorInstance_Detail = InstanceProfileName, IPAddress = SourceIpAddress
)
)
| extend timestamp = StartTimeUtc, UserName = tostring(split(User, '@', 0)[0]), UPNSuffix = tostring(split(User, '@', 1)[0])

YAML

description: |
    'Multi-Factor Authentication (MFA) helps prevent credential compromise. This alert identifies when an attempt has been made to deactivate MFA for a user.'
kind: Scheduled
tactics:
- CredentialAccess
- Persistence
requiredDataConnectors:
- connectorId: AzureActiveDirectory
  dataTypes:
  - AuditLogs
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Cloud Identity Threat Protection Essentials/Analytic Rules/MFADisable.yaml
severity: Medium
name: Multi-Factor Authentication Disabled for a User
triggerThreshold: 0
queryPeriod: 1h
query: |
  (union isfuzzy=true
  (AuditLogs
  | where OperationName =~ "Disable Strong Authentication"
  | extend _parsedIntiatedByUser = parse_json(tostring(InitiatedBy.user))
  | extend _parsedIntiatedByApp = parse_json(tostring(InitiatedBy.app))
  | extend IPAddress = tostring(_parsedIntiatedByUser.ipAddress)
  | extend InitiatedByUser = iff(isnotempty(tostring(_parsedIntiatedByUser.userPrincipalName)),
   tostring(_parsedIntiatedByUser.userPrincipalName), tostring(_parsedIntiatedByApp.displayName))
  | extend Targetprop = todynamic(TargetResources)
  | extend TargetUser = tostring(Targetprop[0].userPrincipalName)
  | summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated) by User = TargetUser, InitiatedByUser , Operation = OperationName , CorrelationId, IPAddress, Category, Source = SourceSystem , AADTenantId, Type
  ),
  (AWSCloudTrail
  | where EventName in~ ("DeactivateMFADevice", "DeleteVirtualMFADevice")
  | extend _parsedRequestParameters = parse_json(RequestParameters)
  | extend InstanceProfileName = tostring(_parsedRequestParameters.InstanceProfileName)
  | extend TargetUser = tostring(_parsedRequestParameters.userName)
  | summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated) by User = TargetUser, Source = EventSource , Operation = EventName , TenantorInstance_Detail = InstanceProfileName, IPAddress = SourceIpAddress
  )
  )
  | extend timestamp = StartTimeUtc, UserName = tostring(split(User, '@', 0)[0]), UPNSuffix = tostring(split(User, '@', 1)[0])  
relevantTechniques:
- T1098
- T1556
id: 65c78944-930b-4cae-bd79-c3664ae30ba7
queryFrequency: 1h
status: Available
triggerOperator: gt
version: 1.0.5
entityMappings:
- entityType: Account
  fieldMappings:
  - columnName: UserName
    identifier: Name
  - columnName: UPNSuffix
    identifier: UPNSuffix
- entityType: IP
  fieldMappings:
  - columnName: IPAddress
    identifier: Address

ARM