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Re: [Full-disclosure] guess what this does..
- To: Cal Leeming <cal@xxxxxxxxxxxxxxxx>
- Subject: Re: [Full-disclosure] guess what this does..
- From: huj huj huj <datskihuj@xxxxxxxxx>
- Date: Mon, 18 Apr 2011 15:28:49 +0200
caldouche
what does your company think about you copy pasting production code on fd?
2011/4/13 Cal Leeming <cal@xxxxxxxxxxxxxxxx>
> 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 <chris@xxxxxxxxxxxxx> 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
>> <uuf6429@xxxxxxxxx>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 <cal@xxxxxxxxxxxxxxxx>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 <uuf6429@xxxxxxxxx
>>>> > 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 <cal@xxxxxxxxxxxxxxxx>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 <rdsears@xxxxxxx> 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" <cal@xxxxxxxxxxxxxxxx>
>>>>>>> To: full-disclosure@xxxxxxxxxxxxxxxxx
>>>>>>> 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/
>
_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/