Absolutely nothing. It really is only meant to stop "stupid bots", which for us, was good enough at the time ;p
On Wed, Apr 13, 2011 at 7:07 PM, Chris M <[email protected]> wrote: > How does all of this stop someone feeding the obfuscated code into jsunpack > and reloading it into a bot application with an inbuilt browser object and > just following links etc? > > > On Wed, Apr 13, 2011 at 3:50 PM, Christian Sciberras <[email protected]>wrote: > >> Is it me or are spammers recruiting more script kiddies as of late? >> Not much of a big deal considering their numbers are on the rise...*ahem* >> anonymous *ahem*. >> >> Chris. >> >> >> >> >> On Wed, Apr 13, 2011 at 4:47 PM, Cal Leeming <[email protected]>wrote: >> >>> Well, the problem was the person(s) running the bots kept bypassing the >>> simple protections such as these. Although it isn't 100% fool proof, it does >>> make things *extremely* difficult for the person(s) with the bots, so much >>> so, that they usually give up, unless they have specifically targeted you >>> for some reason. >>> >>> So, instead we created hundreds of these little JS chunks, all with >>> different lookup tables applied, and cycled them on an hourly basis. It >>> meant if they wanted to continuously bot the service, they would have to de >>> obfuscate the protection code, or find a mathmatical/bruteforce attack that >>> would generate the seedkey for them. It would either involve manual >>> intervention or code modification on the bot to make it work.. I'd >>> have preferred to have added captcha, but there was a reasonable explanation >>> as to why the client didn't want it. >>> >>> Either way, once we put this in, they gave up pretty quickly lol. >>> >>> >>> On Wed, Apr 13, 2011 at 3:29 PM, Christian Sciberras >>> <[email protected]>wrote: >>> >>>> Cal /Ryan, >>>> >>>> I'm not sure what you're trying to achieve. >>>> If we're talking about absolutely stupid bots, the following easily >>>> defeats them: >>>> <form> >>>> <stuff/> >>>> <script type=text/javascript>document.write('<input >>>> type="hidden" name="access" value="code"/>');</script> >>>> <form> >>>> >>>> I suppose you could obfuscate it all if you wanted to cater for script >>>> kiddies. >>>> But considering this is very weak protection (as opposed to proper >>>> captcha), I'm not sure if it's even worthwhile. >>>> One of the ways I can see this work is against automated, "JS-ignorant", >>>> MITM systems. >>>> >>>> As indeed is true, you should never trust the end user. >>>> But in a MITM scenario, the user we're not trusting is the one >>>> conducting the attack, not the other. >>>> >>>> Chris. >>>> >>>> >>>> >>>> On Wed, Apr 13, 2011 at 1:07 PM, Cal Leeming <[email protected]>wrote: >>>> >>>>> Lol, I've just realised something.. I didn't include the seed key >>>>> variable itself, so this code would have been pretty much useless on it >>>>> own >>>>> *DOH*. >>>>> >>>>> So, here's something else a bit tasty.. this is the server side code >>>>> used to check and create the seedkey itself (secret lookup table has been >>>>> changed obv.). >>>>> >>>>> This code allows seedkeys to be generated from epoch time. Now, >>>>> cryptographically I don't know how "sane" this is, but I'm fairly sure >>>>> that >>>>> if the lookup table contained large integers it would become almost >>>>> impossible to do a pattern based brute force. I actually had quite a lot >>>>> of >>>>> fun trying to break my own code. :D >>>>> >>>>> PS) you have been awarded 1 internets. >>>>> >>>>> >>>>> function get_valid_keys() { >>>>> // Create key store >>>>> $_s = array(); >>>>> >>>>> // Create valid key ranges (+900 seconds) >>>>> for($x=300;$x>=900;$x+=300): >>>>> $_s[] = $this->create_key($offset=$x); >>>>> endfor; >>>>> >>>>> // Create valid key ranges (-900 seconds) >>>>> for($x=300;$x>=-900;$x-=300): >>>>> $_s[] = $this->create_key($offset=$x); >>>>> endfor; >>>>> >>>>> $_s[] = $this->create_key(); >>>>> >>>>> return $_s; >>>>> } >>>>> >>>>> function create_packed_key() { >>>>> // Create a new valid key >>>>> $key = $this->create_key(); >>>>> >>>>> // Now generate the packed key >>>>> $k = array(); >>>>> // Now convert it into an array >>>>> for($x=0;$x<strlen($key);$x++): >>>>> $_v = unpack("H*", $key[$x]); >>>>> $k[]='\x'.$_v[1]; >>>>> endfor; >>>>> >>>>> // Okay, here is your brand new shiney key, sir :) >>>>> $m = '"'.implode('","', $k).'"'; >>>>> $m = strrev($m); >>>>> $_m = array(); >>>>> for($x=0;$x<strlen($m);$x++): >>>>> $_m[]=$m[$x]; >>>>> endfor; >>>>> return json_encode(implode("ZPAK", $_m)); >>>>> } >>>>> >>>>> function create_key($offset=0) { >>>>> // Secret key table, used to mix up the seed >>>>> $enc = array( >>>>> 0 => "67892", >>>>> 1 => "3953", >>>>> 2 => "49474", >>>>> 3 => "494755", >>>>> 4 => "30585", >>>>> 5 => "30582", >>>>> 6 => "20485", >>>>> 7 => "20486", >>>>> 8 => "97294", >>>>> 9 => "10284" >>>>> ); >>>>> >>>>> // Generate new seed >>>>> $time = time(); >>>>> if ($offset): >>>>> $time=$time+$offset; >>>>> endif; >>>>> $c=(int)($time/$this->_security_key_refresh); >>>>> $_c = "$c"; >>>>> >>>>> // Extract the last 5 digits of the number >>>>> $char1 = substr($_c, strlen($c)-1, 1); >>>>> $char2 = substr($_c, strlen($c)-2, 1); >>>>> $char3 = substr($_c, strlen($c)-3, 1); >>>>> $char4 = substr($_c, strlen($c)-4, 1); >>>>> $char5 = substr($_c, strlen($c)-5, 1); >>>>> >>>>> // Lookup the modifier from the secret key table >>>>> $mt1 = $enc[$char1]; >>>>> $mt2 = $enc[$char2]; >>>>> $mt3 = $enc[$char3]; >>>>> $mt4 = $enc[$char4]; >>>>> $mt5 = $enc[$char5]; >>>>> >>>>> // Generate a new key, based on the modifiers >>>>> $key = round((($c+$mt1) + ($c+$mt2) + ($c+$mt3) + ($c+$mt4) + >>>>> ($c+$mt5))/256); >>>>> $key = "$key"; >>>>> return $key; >>>>> } >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> On Wed, Apr 13, 2011 at 3:56 AM, Ryan Sears <[email protected]> wrote: >>>>> >>>>>> Me thinks I may have it right (mostly)... >>>>>> >>>>>> It seems to be some jquery to append a hidden input element to the >>>>>> "theform" id (presumably a form on the page ;) ) called "seedkey", and >>>>>> has a >>>>>> value of whatever t is evaluated to (which I'm still stuck on as I don't >>>>>> know jquery much at all, so I can't figure out the s[] array, but I know >>>>>> it >>>>>> has something to do with the bracket notation...). >>>>>> >>>>>> ================================================= >>>>>> += Orig =+ >>>>>> $(function () { >>>>>> var _0xafd3 = ["\x74\x20\x3D\x20\x22", "", "\x6A\x6F\x69\x6E", >>>>>> "\x72\x65\x76\x65\x72\x73\x65", "\x73\x70\x6C\x69\x74", >>>>>> "\x72\x65\x70\x6C\x61\x63\x65", "\x22"]; >>>>>> >>>>>> eval(_0xafd3[0] + s[_0xafd3[5]](/ZPAK/gi, >>>>>> _0xafd3[1])[_0xafd3[5]](/\",\"/gi, _0xafd3[1])[_0xafd3[5]](/\"/gi, >>>>>> _0xafd3[1])[_0xafd3[4]](_0xafd3[1])[_0xafd3[3]]()[_0xafd3[2]](_0xafd3[1]) >>>>>> + >>>>>> _0xafd3[6]); >>>>>> var _0x5bfa = ["\x3C\x69\x6E\x70\x75\x74\x20\x2F\x3E", >>>>>> "\x74\x79\x70\x65", "\x68\x69\x64\x64\x65\x6E", "\x61\x74\x74\x72", >>>>>> "\x6E\x61\x6D\x65", "\x73\x65\x65\x64\x6B\x65\x79", >>>>>> "\x76\x61\x6C\x75\x65", >>>>>> "\x61\x70\x70\x65\x6E\x64", "\x23\x74\x68\x65\x66\x6F\x72\x6D"]; >>>>>> _n = $(_0x5bfa[0]); >>>>>> _n[_0x5bfa[3]](_0x5bfa[1], _0x5bfa[2]); >>>>>> _n[_0x5bfa[3]](_0x5bfa[4], _0x5bfa[5]); >>>>>> _n[_0x5bfa[3]](_0x5bfa[6], t); >>>>>> $(_0x5bfa[8])[_0x5bfa[7]](_n); >>>>>> }); >>>>>> >>>>>> += De-obfuscated =+ >>>>>> $(function () { >>>>>> var _0xafd3 = ['t = "', '', 'join', 'reverse', 'split', >>>>>> 'replace', '"']; >>>>>> var _0x5bfa = ['<input />', 'type', 'hidden', 'attr', 'name', >>>>>> 'seedkey', 'value', 'append', '#theform']; >>>>>> >>>>>> eval('t = "' + s['replace'](/ZPAK/gi, '')['replace'](/\",\"/gi, >>>>>> '')['replace'](/\"/gi, '')['split']('')['reverse']()['join']('') + '"'); >>>>>> >>>>>> _n = $('<input />'); >>>>>> _n['attr']('type', 'hidden'); >>>>>> _n['attr']('name', 'seedkey'); >>>>>> _n['attr']('value', t); >>>>>> $('#theform')['append'](_n); >>>>>> }); >>>>>> >>>>>> ================================================= >>>>>> >>>>>> Fun stuffs. I can haz a internetz? :-P >>>>>> >>>>>> Ryan >>>>>> >>>>>> >>>>>> ----- Original Message ----- >>>>>> From: "Cal Leeming" <[email protected]> >>>>>> To: [email protected] >>>>>> Sent: Tuesday, April 12, 2011 5:28:22 PM GMT -05:00 US/Canada Eastern >>>>>> Subject: [Full-disclosure] guess what this does.. >>>>>> >>>>>> $(function() { >>>>>> var >>>>>> >>>>>> _0xafd3=["\x74\x20\x3D\x20\x22","","\x6A\x6F\x69\x6E","\x72\x65\x76\x65\x72\x73\x65","\x73\x70\x6C\x69\x74","\x72\x65\x70\x6C\x61\x63\x65","\x22"];eval(_0xafd3[0]+s[_0xafd3[5]](/ZPAK/gi,_0xafd3[1])[_0xafd3[5]](/\",\"/gi,_0xafd3[1])[_0xafd3[5]](/\"/gi,_0xafd3[1])[_0xafd3[4]](_0xafd3[1])[_0xafd3[3]]()[_0xafd3[2]](_0xafd3[1])+_0xafd3[6]); >>>>>> var >>>>>> >>>>>> _0x5bfa=["\x3C\x69\x6E\x70\x75\x74\x20\x2F\x3E","\x74\x79\x70\x65","\x68\x69\x64\x64\x65\x6E","\x61\x74\x74\x72","\x6E\x61\x6D\x65","\x73\x65\x65\x64\x6B\x65\x79","\x76\x61\x6C\x75\x65","\x61\x70\x70\x65\x6E\x64","\x23\x74\x68\x65\x66\x6F\x72\x6D"];_n=$(_0x5bfa[0]);_n[_0x5bfa[3]](_0x5bfa[1],_0x5bfa[2]);_n[_0x5bfa[3]](_0x5bfa[4],_0x5bfa[5]);_n[_0x5bfa[3]](_0x5bfa[6],t);$(_0x5bfa[8])[_0x5bfa[7]](_n); >>>>>> }); >>>>>> >>>>>> enjoy ;p >>>>>> >>>>>> ps) yes I obfuscated this, and no it doesn't contain any nasties. >>>>>> >>>>>> _______________________________________________ >>>>>> Full-Disclosure - We believe in it. >>>>>> Charter: http://lists.grok.org.uk/full-disclosure-charter.html >>>>>> Hosted and sponsored by Secunia - http://secunia.com/ >>>>>> >>>>> >>>>> >>>>> _______________________________________________ >>>>> Full-Disclosure - We believe in it. >>>>> Charter: http://lists.grok.org.uk/full-disclosure-charter.html >>>>> Hosted and sponsored by Secunia - http://secunia.com/ >>>>> >>>> >>>> >>> >> >> _______________________________________________ >> Full-Disclosure - We believe in it. >> Charter: http://lists.grok.org.uk/full-disclosure-charter.html >> Hosted and sponsored by Secunia - http://secunia.com/ >> > > > > -- > I’m a hot-wired, heat seeking, warm-hearted cool customer, voice activated > and bio-degradable. I interface with my database, my database is in > cyberspace, so I’m interactive, I’m hyperactive and from time to time I’m > radioactive. >
_______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
