Broadcom has started to publish their own Vendor Product STIG – TSS for z/OS, how to properly utilize TSS to secure the z/OS Mainframe. STIG Articles provide documented z/OS Mainframe Security Controls to help you move forward in securing your mainframes.
The Broadcom Vendor TSS STIG for z/OS can be found at: https://techdocs.broadcom.com/us/en/ca-mainframe-software/security/ca-top-secret-for-z-os/16-0/using-stig-articles.html