Admin UI Returns 404 error after jdk point version upgrade and service restart

After a recent RHEL O/S upgrade,  the admin UI was returning a 404 error even thought the SOLR service was up and running.  Further investigation suggested that the root cause was the java version used to start the service was to blame.  Since we were seeing the issue only on QA and PROD had not yet been patched, the Linux admin restarted the service on the affected server using the pre-ugrade version of the JDK, which solved the issue.

We're wondering why this would fail on  a minor point version upgrade.

More details:

Pre-upgrade - RHEL 7.4 , openjdk v 1.8.0_144

Post-upgrade - RHEL 7.5, openjdk v 1.8.0_171-8 (the service started, but admin UI not working)

Solr version 6.6.0