Could the existing Apache Tomcat in UIM Servers be upgraded independently to resolve vulnerability issues?

Release:
Component: CAUIM

No, upgrading individual components to resolve vulnerability issues is not supported.

You would need to open support case with your UIM release, CVE Number(s) for the vulnerability(ies) reported for us to check if there is a workaround (or) fix available

You could also up vote the idea created for the same clicking here