ByteHook on 1:36 PM 11/01/2024: It was interesting, although I didn't get to the bottom of the key.
According to my observations, only numbers should be used instead of N, and the format "12345-TOM-1234567-12345" is incorrect.
Next, I found the string "0D0A0C0F1C1A0A171C170C17160F191E", with it I collected the first working key: "17171-TOM-1717171-17171", then I started experimenting with the key, came to the conclusion that the maximum allowable key value: "17171-TOM-2222222-22222", changing the first 5 digits leads to the wrong key.
Perhaps he performs operations only with the first 5 digits, and then checks them.
Correct! Here is your flag: WPVUF@PMFMVMLUCD
My keygen version: https://pastebin.com/WQs3UVB0
dzwassim95 on 9:08 PM 11/03/2024: i didnt get it , and i found the "0D0A0C0F1C1A0A171C170C17160F191E" thing , but i didnt know im supposed to use it as a reverence to find the answer, i got frustrated and i patched the hell out of it:
Enter the serial number (format: NNNNN-TOM-NNNNNNN-NNNNN): 11111-TOM-1111111-11111
Correct! Here is your flag: WPVUF@PMFMVMLUCD
haze303 on 2:38 PM 11/10/2024: The Crackme only checks for the correct format and length auf the key. Afterwards only the first five digits are relevant.
005F151E call
is where the magic happens. In particular:
005F128A mov ecx,7
005F128F idiv ecx #Modulo operation with 7
005F1291 test edx,edx #If varFirstFiveDigits % 7 == 0
005F1293 je app.5F12B9 #Jump to the good stuff or to the bad stuff
Here my keygen: https://pastebin.com/ucdLrTVc
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