Azure External Guest User Invitation
editAzure External Guest User Invitation
editIdentifies an invitation to an external user in Azure Active Directory (AD). Azure AD is extended to include collaboration, allowing you to invite people from outside your organization to be guest users in your cloud account. Unless there is a business need to provision guest access, it is best practice avoid creating guest users. Guest users could potentially be overlooked indefinitely leading to a potential vulnerability.
Rule type: query
Rule indices:
- filebeat-*
Severity: low
Risk score: 21
Runs every: 5 minutes
Searches indices from: now-25m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Cloud
- Azure
- Continuous Monitoring
- SecOps
- Identity and Access
Version: 1
Added (Elastic Stack release): 7.10.0
Rule authors: Elastic
Rule license: Elastic License
Potential false positives
editGuest user invitations may be sent out by a system or network administrator. Verify whether the username, hostname, and/or resource name should be making changes in your environment. Guest user invitations from unfamiliar users or hosts should be investigated. If known behavior is causing false positives, it can be exempted from the rule.
Investigation guide
editThe Azure Filebeat module must be enabled to use this rule.
Rule query
editevent.dataset:azure.auditlogs and azure.auditlogs.operation_name:"Invite external user" and azure.auditlogs.properties.target_resources.*.display_name:guest and event.outcome:Success
Threat mapping
editFramework: MITRE ATT&CKTM
-
Tactic:
- Name: Initial Access
- ID: TA0001
- Reference URL: https://attack.mitre.org/tactics/TA0001/
-
Technique:
- Name: Valid Accounts
- ID: T1078
- Reference URL: https://attack.mitre.org/techniques/T1078/
-
Tactic:
- Name: Persistence
- ID: TA0003
- Reference URL: https://attack.mitre.org/tactics/TA0003/
-
Technique:
- Name: Valid Accounts
- ID: T1078
- Reference URL: https://attack.mitre.org/techniques/T1078/