Description
It is well known that the plain RSA primitive is multiplicatively homomorphic: the ciphertext corresponding to the product of two plaintexts is the product of the two ciphertexts. After several years of work, our researchers have obtained a major breakthrough: they have figured out how to compute the ciphertext corresponding to the sum of two plaintexts using only the original ciphertexts and the public key. This makes the RSA cryptosystem fully homomorphic!
The details of their work is still confidential. However, we’re pleased to share an emulator of this “Fully Homomorphic RSA”, so that the community can already start to explore all the possibilities it offers.
Files
- docker-compose.yml
-
fully-homomorphic-rsa.py
727 B – 44b7853ae2897a83d5035b3b219d6f53a087eed204fe950a03e8e0f96ea934ea
Author
Challenge Instructions
- First, download docker-compose.yml:
curl https://hackropole.fr/challenges/fcsc2026-crypto-fully-homomorphic-rsa/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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