Login to AWS Management Console without MFA

Back


Id	d25b1998-a592-4bc5-8a3a-92b39eedb1bc
Rulename	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 adminsitrative 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	Scheduled
Query frequency	1d
Query period	1d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_ConsoleLogonWithoutMFA.yaml
Version	1.0.5
Arm template	d25b1998-a592-4bc5-8a3a-92b39eedb1bc.json

KQL

AWSCloudTrail
| where EventName =~ "ConsoleLogin"
| extend MFAUsed = tostring(parse_json(AdditionalEventData).MFAUsed), LoginResult = tostring(parse_json(ResponseElements).ConsoleLogin), indexId = indexof(tostring(UserIdentityPrincipalid),":")
| 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, indexId
| extend timestamp = StartTimeUtc

YAML

relevantTechniques:
- T1078
entityMappings:
- fieldMappings:
  - columnName: AccountName
    identifier: Name
  - columnName: AccountUPNSuffix
    identifier: UPNSuffix
  - columnName: RecipientAccountId
    identifier: CloudAppAccountId
  entityType: Account
- fieldMappings:
  - columnName: SourceIpAddress
    identifier: Address
  entityType: IP
triggerThreshold: 0
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 adminsitrative 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.'  
requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
- connectorId: AWSS3
  dataTypes:
  - AWSCloudTrail
triggerOperator: gt
version: 1.0.5
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_ConsoleLogonWithoutMFA.yaml
id: d25b1998-a592-4bc5-8a3a-92b39eedb1bc
queryFrequency: 1d
query: |
  AWSCloudTrail
  | where EventName =~ "ConsoleLogin"
  | extend MFAUsed = tostring(parse_json(AdditionalEventData).MFAUsed), LoginResult = tostring(parse_json(ResponseElements).ConsoleLogin), indexId = indexof(tostring(UserIdentityPrincipalid),":")
  | 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, indexId
  | extend timestamp = StartTimeUtc  
severity: Low
status: Available
queryPeriod: 1d
name: Login to AWS Management Console without MFA
tactics:
- DefenseEvasion
- PrivilegeEscalation
- Persistence
- InitialAccess
kind: Scheduled

ARM