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x0rz Keygen Me


Go to solution Solved by sama,

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Posted

Difficulty : 7-8
Language : Delphi
Platform : Windows x32
OS Version : All Windows 
Packer / Protector : None and No Crypto

Description :

Rules : no patch, only working keygen or a valid serial for your name...

Good luck

Screenshot :

N1rr8N.png

 

x0rz Keygen ME.rar

  • Like 2
Posted (edited)

Just a quick overview :)

thanks for the challange

 

Name: John

Key: F6FBF830-0D910F71-0A79EF4F-0D631D6E

2uQVu.png

enjoy

Edited by sama
  • Like 3
Posted
15 hours ago, sama said:

Just a quick overview :)

thanks for the challange

 

Name: John

Key: F6FBF830-0D910F71-0A79EF4F-0D631D6E

2uQVu.png

enjoy

Thx for Solution. Can you please explain, how to you solved it? 

  • Solution
Posted
4 hours ago, s3rh47 said:

Thx for Solution. Can you please explain, how to you solved it? 

sure there is no secret in it :)

serial parts calling P1-P2-P3-P4

P1 is based on name with a bit xor, the tricky is P2 and P3 but simple to recognize

anway P2 and P3 are xored with name based value then turned into decimal

now for P2 take last 6 digits which must be a Carmichael pseudo prime (ODD, at least 3 factors) and must be > then 100.000

to pass the first check and to pass second check the whole P2 (after the xor) must be prime!

Same is for P3 except that the Carmichael pseudo prime are now the first 6 digits!

as for P4 is a simple calculation xor and add (if i remember right) and game is done.

 

have a nice day

  • Like 2
Posted
5 minutes ago, sama said:

sure there is no secret in it :)

serial parts calling P1-P2-P3-P4

P1 is based on name with a bit xor, the tricky is P2 and P3 but simple to recognize

anway P2 and P3 are xored with name based value then turned into decimal

now for P2 take last 6 digits which must be a Carmichael pseudo prime (ODD, at least 3 factors) and must be > then 100.000

to pass the first check and to pass second check the whole P2 (after the xor) must be prime!

Same is for P3 except that the Carmichael pseudo prime are now the first 6 digits!

as for P4 is a simple calculation xor and add (if i remember right) and game is done.

 

have a nice day

Thank you for the solution.

Posted
On 28.6.2017 at 2:03 PM, sama said:

sure there is no secret in it :)

serial parts calling P1-P2-P3-P4

P1 is based on name with a bit xor, the tricky is P2 and P3 but simple to recognize

anway P2 and P3 are xored with name based value then turned into decimal

now for P2 take last 6 digits which must be a Carmichael pseudo prime (ODD, at least 3 factors) and must be > then 100.000

to pass the first check and to pass second check the whole P2 (after the xor) must be prime!

Same is for P3 except that the Carmichael pseudo prime are now the first 6 digits!

as for P4 is a simple calculation xor and add (if i remember right) and game is done.

 

have a nice day

hey Sama again thx for solution but i want to ask you something

xorz  has forgot a string in KeygenMe under Procedure of Carmichaeal Algorithm .. That was "CARMI".

have you got a Tipp from this String or you have solved without this string ? 
 

Posted (edited)

indeed i saw that string but even without it

here are the points

 

2uVx3.png

get the squareroot

then in next loop checking if CGD is 1

2uVx2.png

 

and then

2uVx4.png

and this is according with what wikipedia tells us: (extract from wiki)

"In number theory, a Carmichael number is a composite number n{\displaystyle n}n which satisfies the modular arithmetic congruence relation:

2uVyp.png

for all integers b which are relatively prime to n. [1] They are named for Robert Carmichael. The Carmichael numbers are the subset K1 of the Knödel numbers."

further information look at https://en.wikipedia.org/wiki/Carmichael_number

 

have a nice day

Edited by sama
  • Like 4

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