Hello,
While noticing the /var/atlassian/application-data/jira directory has 700 access drwx, can the file: dbconfig.xml which has 644 in this directory, operate successfully if the permissions were set to 600 vs. 644? The same user that owns dbconfig.xml is the one that starts up the JIRA service on Linux.
Reason for the question is safeguarding the permissions as much possible down to the file itself