Programming 3 almost decrypted need some help

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Programming 3 almost decrypted need some help

Post by BlayzeX on Mon Dec 27, 2010 3:30 am
([msg=51204]see Programming 3 almost decrypted need some help[/msg])

Ok I am a PHP noob, but I thought I would give this a try.

So this works to get the FIRST CHARACTER decoded properly, BUT each character after that is off. Where I THINK the problem lies is the intMD5Total which CHANGES each time. Its not the password part that throws it off its the $strSTRING that is the key... that MD5 when ENCRYPTED is based off the md5 of the ORIGINAL message we are trying to decode.

So is that correct. Is this a password and MD5 bruteforce as well??

OR am i completely off and need to fix something else in my logic of decrypting this... Any help would be appreciated.

ANY... I am not asking for the actual program/bruteforcer.

-- Mon Dec 27, 2010 5:15 am --

ok SWEET....fixed the issue with decrypting it.....

now is there a way to translate this to vb.net...lol.. I tried but am stuck at "0x0" does this just turn it to hexidecimal or something.....

any extra assistance would be great...

-- Mon Dec 27, 2010 10:08 am --

Ok I got the encryption and decryption down....

I ran it with all combinations of 3 and all combinations of 4... the 4 combinations with lowercase and numbers takes over 120 seconds...

is there a hint on the password length/characters.... just wondering... will keep testing...
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Re: Programming 3 almost decrypted need some help

Post by TheMindRapist on Thu Dec 30, 2010 1:21 pm
([msg=51364]see Re: Programming 3 almost decrypted need some help[/msg])

BlayzeX wrote:Ok I got the encryption and decryption down....

I ran it with all combinations of 3 and all combinations of 4... the 4 combinations with lowercase and numbers takes over 120 seconds...

is there a hint on the password length/characters.... just wondering... will keep testing...

If you solved the challenge on your own then I don't think you should have trouble identifying obvious patterns in the serials.
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Re: Programming 3 almost decrypted need some help

Post by BlayzeX on Sun Jan 23, 2011 3:08 am
([msg=52673]see Re: Programming 3 almost decrypted need some help[/msg])

Sorry took a break from this...

I have the decryption function down.

Now in the challenge, the serials are encrypted with a password. So the problem is that the first 32 characters use the password MD5Hash, the rest do not so that leaves a difference of max 15 ..... then intMD5total starts out using the password hash and from then on everything from previous is used to get intMD5total.. that difference is 480.

Now using the md5 of 0 to 480 the highest difference is 167, lowest i think is 67, but the other half/part of that is the possible serials it could be.

If anyone could give me a damn hint.. I have tried brute forcing letter/number combinations (not for the password, but actual serials to see if i can somehow get it working...

I took the last serial alone, I know the last 20 is the serial and the ending character, so i started with 21 which is the same character found the difference and tried to apply it to a modified decryption function setting in that difference and then try to find which of the letters numbers would get from character 20 to 19 to 18 and see if it would work with the known "-" and OEM, etc.. and nothing.... that 15 or each little number difference can throw it off by one or more letters...

hmmm I might be over thinking it or under thinking it... if possible a hint..lol...
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