Another RCE in Print Spooler Mayhem awaits

Microsoft acknowledged yet another remote code execution vulnerability in the Windows Print Spooler component, after a day of releasing arch tuesday updates adding that it’s working to remediate the issue in an upcoming security update.

Tracked as CVE-2021-36958 (CVSS score: 7.3), the unpatched flaw is the latest to join a list of bugs collectively known as PrintNightmare that have plagued the printer service and come to light in recent months.

RCE vulnerability exists when the Windows Print Spooler service improperly performs privileged file operations in its out-of-band bulletin, echoing the vulnerability details for CVE-2021-34481.

An attacker who successfully exploited this vulnerability could run arbitrary code with SYSTEM privileges. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

Microsoft Statement

Windows Print Spooler RCE Vulnerability
It’s worth noting that the Windows maker has since released updates to change the default Point and Print default behavior, effectively barring non-administrator users from installing or updating new and existing printer drivers using drivers from a remote computer or server without first elevating themselves to an administrator.

Microsoft is recommends users to stop and disable the Print Spooler service to prevent malicious actors from exploiting the vulnerability. The CERT Coordination Center, in a vulnerability note, is also advising users to block outbound SMB traffic to prevent connecting to a malicious shared printer.

Seems Spooler and Threat vectors having a valentine relationship for a longer running duration.