CVE-2021-20335
For MongoDB Ops Manager 4.2.X with multiple OM application servers, that have SSL turned on for their MongoDB processes, the upgrade to MongoDB Ops Manager 4.4.X triggers a bug where Automation thinks SSL is being turned off, and can disable SSL temporarily for members of the cluster. This issue is temporary and eventually corrects itself after MongoDB Ops Manager instances have finished upgrading to MongoDB Ops Manager 4.4. In addition, customers must be running with clientCertificateMode=OPTIONAL / allowConnectionsWithoutCertificates=true to be impacted.
Source: CVE-2021-20335