classes/Url.php in Justin Hagstrom AutoIndex PHP Script before 2.2.4 allows remote attackers to cause a denial of service (CPU and memory consumption) via a %00 sequence in the dir parameter to index.php, which triggers an erroneous "recursive calculation."
https://exchange.xforce.ibmcloud.com/vulnerabilities/38437
http://www.securityfocus.com/bid/26410
http://www.securityfocus.com/archive/1/483592/100/0/threaded