The Wildfly 10 build creates two "auth" directories, one under each config:

WILDFLY_HOME/domain/tmp: auth
WILDFLY_HOME/standalone/tmp: auth

while in Wildfly 8 there was a single "auth" dir at top-level:

WILDFLY_HOME/auth

Apparently there is no changes to the code changing where the 'auth' directory is looked for so this may be an issue with the new build system (or was an issue with the old one, but that is not documented). And as the code creates it if it does not exist this may have been unnoticed in either case.

We need to get this sorted out asap so we make sure these directories (or directory) are (or is) created with the right permissions.