Description
The MegaSecure company provides a secure server allowing to execute operations while controlling its energy consumption.
The server allows to execute commands in a secure way. Indeed, it relies on a secure component to verify the signature of any received command before executing it.
The Python code equivalent to the signature is as follows:
def sign(self, m):
return pow(int(sha256(m), 16), self.d, self.N)
and its verification is done as follows:
def verif(self, m, s):
return int(sha256(m), 16) == pow(int(s), self.e, self.N)
However, being still in development, only two commands (ls -la flag.txt and cat flag.txt) are available.
Also, it has been noticed that the server presents strange behaviours in some configurations.
Files
Author
Challenge Instructions
- First, download docker-compose.yml:
curl https://hackropole.fr/challenges/fcsc2022-hardware-secure-green-server/docker-compose.public.yml -o docker-compose.yml - Launch the challenge by executing in the same folder:
docker compose up - Then, in another console, access the challenge with Netcat:
nc localhost 4000
In case you encounter problems, please consult the FAQ.
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