AWS STS AssumeRole with New MFA Device
editAWS STS AssumeRole with New MFA Device
editIdentifies when a user has assumed a role using a new MFA device. Users can assume a role to obtain temporary credentials and access AWS resources using the AssumeRole API of AWS Security Token Service (STS). While a new MFA device is not always indicative of malicious behavior it should be verified as adversaries can use this technique for persistence and privilege escalation.
Rule type: new_terms
Rule indices:
- filebeat-*
- logs-aws.cloudtrail-*
Severity: low
Risk score: 21
Runs every: 5m
Searches indices from: None (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References:
Tags:
- Domain: Cloud
- Data Source: AWS
- Data Source: Amazon Web Services
- Data Source: AWS STS
- Use Case: Identity and Access Audit
- Tactic: Privilege Escalation
- Tactic: Persistence
- Tactic: Lateral Movement
Version: 1
Rule authors:
- Elastic
Rule license: Elastic License v2
Investigation guide
editSetup
editThe AWS Fleet integration, Filebeat module, or similarly structured data is required to be compatible with this rule.
Rule query
editevent.dataset:aws.cloudtrail
and event.provider:sts.amazonaws.com
and event.action:(AssumeRole or AssumeRoleWithSAML or AssumeRoleWithWebIdentity)
and event.outcome:success
and user.id:*
and aws.cloudtrail.flattened.request_parameters.serialNumber:*
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Persistence
- ID: TA0003
- Reference URL: https://attack.mitre.org/tactics/TA0003/
-
Technique:
- Name: Modify Authentication Process
- ID: T1556
- Reference URL: https://attack.mitre.org/techniques/T1556/
-
Sub-technique:
- Name: Multi-Factor Authentication
- ID: T1556.006
- Reference URL: https://attack.mitre.org/techniques/T1556/006/
-
Tactic:
- Name: Privilege Escalation
- ID: TA0004
- Reference URL: https://attack.mitre.org/tactics/TA0004/
-
Technique:
- Name: Abuse Elevation Control Mechanism
- ID: T1548
- Reference URL: https://attack.mitre.org/techniques/T1548/
-
Tactic:
- Name: Lateral Movement
- ID: TA0008
- Reference URL: https://attack.mitre.org/tactics/TA0008/
-
Technique:
- Name: Use Alternate Authentication Material
- ID: T1550
- Reference URL: https://attack.mitre.org/techniques/T1550/
-
Sub-technique:
- Name: Application Access Token
- ID: T1550.001
- Reference URL: https://attack.mitre.org/techniques/T1550/001/