Constant java.lang.NullPointerException in catalina logs

“ERROR”, 14/05/2019, 14:24:04,
lucee.runtime.exp.NativeException: java.lang.NullPointerException
Caused by: java.lang.NullPointerException

I’m not getting any details other than the above. This has occurred since the upgrade from

The system appears to be stable but these errors are very regular i.e. numerous within a minutes interval.

Servlet Container Apache Tomcat/8.0.36
Java 1.8.0_121 (Oracle Corporation) 64bit
Host Name
OS Linux (3.10.0-514.6.2.el7.x86_64) 64bit
Architecture 64bit