Sergey Lyubka Simple HTTPD (shttpd) 1.38 and earlier on Windows allows remote attackers to download arbitrary CGI programs or scripts via a URI with an appended (1) '+' character, (2) '.' character, (3) %2e sequence (hex-encoded dot), or (4) hex-encoded character greater than 0x7f. NOTE: the %20 vector is already covered by CVE-2007-3407.
https://www.exploit-db.com/exploits/4700
http://www.securityfocus.com/archive/1/484761/100/0/threaded