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 :

 

x0rz Keygen ME.rar

Just a quick overview

thanks for the challange

 

Name: John

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

enjoy

Edited June 27, 20178 yr by sama

15 hours ago, sama said:

Just a quick overview

thanks for the challange

 

Name: John

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

enjoy

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

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

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.

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 ? 
 

indeed i saw that string but even without it

here are the points

 

get the squareroot

then in next loop checking if CGD is 1

 

and then

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} which satisfies the modular arithmetic congruence relation:

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 June 30, 20178 yr by sama