The tool reads the encrypted bytes. Using a cryptography library (like OpenSSL or Bouncy Castle), it applies the inverse of the encryption algorithm.
The process typically involves using a specialized tool or service that knows the specific encryption keys and algorithms (often AES-based) used by the JDownloader framework, which popularized the format. Encryption Keys dlc decrypt
If you own the key, decrypting your own property is a technical curiosity. If you are hunting for a master key to everything on Steam, you are sailing into illegal waters. Always remember: if a tool promises to decrypt DLC for free, the real price might be your account security or a lawsuit. The tool reads the encrypted bytes
