NRT Login to AWS Management Console without MFA

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Id	0ee2aafb-4500-4e36-bcb1-e90eec2f0b9b
Rulename	NRT Login to AWS Management Console without MFA
Description	Multi-Factor Authentication (MFA) helps you to prevent credential compromise. This alert identifies logins to the AWS Management Console without MFA. You can limit this detection to trigger for administrative accounts if you do not have MFA enabled on all accounts. This is done by looking at the eventName ConsoleLogin and if the AdditionalEventData field indicates MFA was NOT used and the ResponseElements field indicates NOT a Failure. Thereby indicating that a non-MFA login was successful.
Severity	Low
Tactics	DefenseEvasion PrivilegeEscalation Persistence InitialAccess
Techniques	T1078
Required data connectors	AWS AWSS3
Kind	NRT
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/NRT_AWS_ConsoleLogonWithoutMFA.yaml
Version	1.0.3
Arm template	0ee2aafb-4500-4e36-bcb1-e90eec2f0b9b.json

KQL

AWSCloudTrail
| where EventName =~ "ConsoleLogin"
| extend MFAUsed = tostring(parse_json(AdditionalEventData).MFAUsed), LoginResult = tostring(parse_json(ResponseElements).ConsoleLogin)
| where MFAUsed !~ "Yes" and LoginResult !~ "Failure"
| where SessionIssuerUserName !contains "AWSReservedSSO"
| extend UserIdentityArn = iif(isempty(UserIdentityArn), tostring(parse_json(Resources)[0].ARN), UserIdentityArn)
| extend UserName = tostring(split(UserIdentityArn, '/')[-1])
| extend AccountName = case( UserIdentityPrincipalid == "Anonymous", "Anonymous", isempty(UserIdentityUserName), UserName, UserIdentityUserName)
| extend AccountName = iif(AccountName contains "@", tostring(split(AccountName, '@', 0)[0]), AccountName),
  AccountUPNSuffix = iif(AccountName contains "@", tostring(split(AccountName, '@', 1)[0]), "")
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated) by EventName, EventTypeName, LoginResult, MFAUsed, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityAccountId,  UserIdentityPrincipalid, UserAgent,
  UserIdentityUserName, SessionMfaAuthenticated, SourceIpAddress, AWSRegion

YAML

version: 1.0.3
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
  entityType: IP
description: |
  'Multi-Factor Authentication (MFA) helps you to prevent credential compromise. This alert identifies logins to the AWS Management Console without MFA.
  You can limit this detection to trigger for administrative accounts if you do not have MFA enabled on all accounts.
  This is done by looking at the eventName ConsoleLogin and if the AdditionalEventData field indicates MFA was NOT used and the ResponseElements field indicates NOT a Failure. Thereby indicating that a non-MFA login was successful.'  
query: |
  AWSCloudTrail
  | where EventName =~ "ConsoleLogin"
  | extend MFAUsed = tostring(parse_json(AdditionalEventData).MFAUsed), LoginResult = tostring(parse_json(ResponseElements).ConsoleLogin)
  | where MFAUsed !~ "Yes" and LoginResult !~ "Failure"
  | where SessionIssuerUserName !contains "AWSReservedSSO"
  | extend UserIdentityArn = iif(isempty(UserIdentityArn), tostring(parse_json(Resources)[0].ARN), UserIdentityArn)
  | extend UserName = tostring(split(UserIdentityArn, '/')[-1])
  | extend AccountName = case( UserIdentityPrincipalid == "Anonymous", "Anonymous", isempty(UserIdentityUserName), UserName, UserIdentityUserName)
  | extend AccountName = iif(AccountName contains "@", tostring(split(AccountName, '@', 0)[0]), AccountName),
    AccountUPNSuffix = iif(AccountName contains "@", tostring(split(AccountName, '@', 1)[0]), "")
  | summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated) by EventName, EventTypeName, LoginResult, MFAUsed, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityAccountId,  UserIdentityPrincipalid, UserAgent,
    UserIdentityUserName, SessionMfaAuthenticated, SourceIpAddress, AWSRegion  
tactics:
- DefenseEvasion
- PrivilegeEscalation
- Persistence
- InitialAccess
severity: Low
name: NRT Login to AWS Management Console without MFA
kind: NRT
status: Available
id: 0ee2aafb-4500-4e36-bcb1-e90eec2f0b9b
requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
- connectorId: AWSS3
  dataTypes:
  - AWSCloudTrail
relevantTechniques:
- T1078
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/NRT_AWS_ConsoleLogonWithoutMFA.yaml

ARM