What does CBC stand for?

The message is encrypted with some block cipher algorithm in cipher block chaining (CBC) mode to create a chain of blocks such that each block depends on the proper encryption of the previous block.

What is CBC mode?

In CBC mode, each block of plaintext is XORed with the previous ciphertext block before being encrypted. This way, each ciphertext block depends on all plaintext blocks processed up to that point. To make each message unique, an initialization vector must be used in the first block.

How does CBC decryption work?

The CBC decryption process works in a similar but distinct way. Contrary to similar decryption methods, the process does not start with the final ciphertext block. In fact, it can all happen simultaneously because all inputs are present. To invert the cipher block chaining procedure, one must essentially reverse the encryption process.

How does CBC work?

One of CBC's key characteristics is that it uses a chaining process that causes the decryption of a block of ciphertext to depend on all the preceding ciphertext blocks. As a result, the entire validity of all preceding blocks is contained in the previous, adjacent ciphertext block.