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90 points
13 Solves
Cryptography
WolfowyCommunity Rating: 5.00 / 5
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Hello!
I have just implemented a super-cool PRNG!
I've used every next generated by it number to XOR every next character in my super-secret message with.
Are you able to retrieve it?
Btw. Biggest possibly generated number by my PRNG is 255.
Psst. The retrieved message would be your flag!
As always, starting with: CTFlearn{...
I'm giving you the PRNG scheme with a brief description (description.png) and a "secretMessage.hex" file with every byte being the corresponding message char inside PRNG.zip file.
First 10 Solvers
| Rank | Username |
|---|---|
| 1 | uynguyen |
| 2 |
Gilad
|
| 3 | ebouteillon |
| 4 | SunTzu |
| 5 | momo1 |
| Rank | Username |
|---|---|
| 6 | spintronix |
| 7 | zharfanf |
| 8 | 3cd54 |
| 9 | Rivit |
| 10 | impulse |
michaelmichael
Wiki title. Once you fully understand the idea of the N mask, you can solve by trial and error with python string and xor skills. You should also be fluid in representing ascii strings in binary format to see what is happening with patterns...
Ichild
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Wolfowy
Great solution :)
Rivit
Very good challenge
Wolfowy
Thank you :)
zharfanf
remember format of the flag
uynguyen
The nice one! We have to do many steps by hand to find the seed key
Wolfowy
Thanks! It depends on an approach ;)