Attack model

Attack models or attack types specify how much information a cryptanalyst has access to when "breaking" or "cracking" an encrypted message, commonly known as codebreaking or cracking the code. Some common attack models are:
The ciphertext-only attack model is the weakest because it implies that the cryptanalyst has just the encoded message.
Different attack models are used for other cryptographic systems, or more generally for all kind of security systems. Examples for such attack models are: