Customer reports that they are using, camel v2.18.1.redhat-000021 with latest FIS 2.0 release and they need to backport the fix of https://issues.apache.org/jira/browse/CAMEL-11229.

Business requirement:

• In the exception handling code an error response is generated using an
  external library. For example using a freemarker template, but this could
  as well be some other library.
  This library could throw an exception. If this is the case we do not want
  to end up in a infite loop and a server crash as a result.

As i see it, CAMEL-11229 seems to be fixed in origin/release-work-2.20.0-fuse-000 branch, as well as 2.18.x branch, but not sure if this fix is part of FIS 2.0 what customer is indicating.