Overview[1]#

In Cryptography Cipher Block Chaining is a mode of operation used for Block Ciphers where 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.

Cipher Block Chaining, typically, to make each message unique, an Initialization Vector must be used in the first block.

Problems with Cipher Block Chaining modes#

Generally speaking, there are problems with the way that TLS uses Block Ciphers in Cipher Block Chaining (CBC) modes and Cipher Block Chaining is considered a Cryptographically Weak Cryptographic Primitive.[2][3]

Lucky 13 attack on Cipher Block Chaining encryption in TLS

More Information#

There might be more information for this subject on one of the following:

• BEAST
• Block Cipher Mode
• CBC
• CBC-MAC
• Galois-Counter Mode
• NIST.SP.800-38

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• [#1] - Cipher Block Chaining (CBC) - based on information obtained 2015-12-07
• [#2] - Lucky Thirteen: Breaking the TLS and DTLS Record Protocols - based on information obtained 2015-12-07
• [#3] - Lucky Thirteen: Breaking the TLS and DTLS Record Protocols (Detailed) - based on information obtained 2015-12-07