Unfortunately currently there is no option available to allow encryption of variables in
"org.ops4j.pax.web.cfg"as there are enhancement requests already raised for the same and is due for JBoss Fuse 7.0 release, However the Jetty Password Utility  can be used for the jetty level password encryption. Users should be able to use the password utility using the following command (
java -cp jetty-all-server-8.1.14.v20131031.jar org.eclipse.jetty.util.security.Password admin password
This should generate output like this:
Users should be able to place these in your properties file.
Unfortunately, there is no way in Fuse to presently do this. This was a feature implemented in Pax Web version 6.0. Here's the request for this, [PAXWEB-1021] Allow Encrypted of password in org.ops4j.pax.web.cfg - OPS4J Issues .
Hence, if you still need to have the encrypted passwords you need to install the pax-web version 6.00 or higher in Fuse.