Xerver 4.17 allows remote attackers to (1) obtain source code of scripts via a request with a trailing "." (dot) or (2) list directory contents via a trailing null character.
https://exchange.xforce.ibmcloud.com/vulnerabilities/22786
https://exchange.xforce.ibmcloud.com/vulnerabilities/22785
https://euvd.enisa.europa.eu/vulnerability/EUVD-2005-3292
http://www.securityfocus.com/bid/15135