The vulnerability has been dubbed PrintNightmare and is tracked as CVE-2021-34527. The flaw is due to the Windows Print Spooler service improperly performing privileged file operations. Microsoft says the flaw can be exploited by an authenticated user calling RpcAddPrinterDriverEx(). When exploited, an attacker gains SYSTEM privileges and can execute arbitrary code, install programs, view, change, or delete data or create new accounts with full user rights.
A vulnerability in the admin web interface could allow an authenticated attacker to upload a custom template to perform an arbitrary code execution. These templates can be used to display customised login and meeting pages and are rendered using the Perl Template Toolkit engine. This engine can be coerced into executing code by creating a new "BLOCK" by abusing the "template" global object to create a new block to be evaluated. The deployed agent will run with ROOT privileges.