Using this command:
openssl smime -encrypt -aes-256-cbc -in input.txt -out output.txt -outform DER yourSslCertificate.pem
I can decrypt (using my private key) an encrypted file (encrypted with my public key). Is there a direct translation to this not using OpenSSL but only .Net 4.5 Framework (or lower) classes. I can use BounceCastle if it helps.
The private key was created using openssl:
openssl req -x509 -nodes -days 100000 -newkey rsa:8912 -keyout private_key.pem -out certificate.pem