Summary
TheRBAC_Admins table within the MSSQL database server controls the additions and deletions to the SMS Admins local security group. That means if a user is inserted into the RBAC_Admins table, then the user’s SID is added to the SMS Admins local security group on the SMS Provider.
Attackers who relay the site server computer account to the MSSQL database server and insert a new user into the RBAC_Admins table will automatically add that user to the SMS Admins local security group.
Defenders can implement custom auditing into the Application or Security log of the MSSQL database server. SQL Server Auditing will track changes on the RBAC_Admins table.
- Within the MSSQL database server, open
SQL Server Management Studio (SSMS), expand your SQL Server instance. - Go to
Security>Audits> Right-click >New Audit. - Configure the audit to log to a file or the event log.
- Create an audit specification to track access to the
RBAC_Adminstable:
- Create a database specific audit:
RBAC_Admins table, an Event ID: 33205 will be generated within the MSSQL database server’s Application log. The following Event ID: 33205 displays the information expected from an "INSERT" into the RBAC_Admins table:
Associated Offensive IDs
- TAKEOVER-1: Hierarchy takeover via NTLM coercion and relay to MSSQL on remote site database
- TAKEOVER-2: Hierarchy takeover via NTLM coercion and relay to SMB on remote site database
- RECON-4: Query client devices via CMPivot
- RECON-5: Locate users via SMS Provider
References
- Garrett Foster, Site Takeover via SCCM’s AdminService API
- Microsoft Learn, Plan for the SMS Provider