!!! Overview[1]
In [Cryptography] [{$pagename}] is a mode of operation used for [Block Ciphers] where each block of plaintext is XORed with the previous [ciphertext] block before being [encrypted|Encryption]. This way, each [ciphertext] block depends on all plaintext blocks processed up to that point. 

[{$pagename}], typically, to make each message unique, an [Initialization Vector] must be used in the first [block].

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

[Lucky 13] [attack] on [{$pagename}] [encryption] in [TLS]

!! More Information
There might be more information for this subject on one of the following:
[{ReferringPagesPlugin before='*' after='\n' }]
----
* [#1] - [Cipher Block Chaining (CBC)|Wikipedia:Block_cipher_mode_of_operation#Cipher_Block_Chaining_.28CBC.29|target='_blank'] - based on information obtained 2015-12-07
* [#2] - [Lucky Thirteen: Breaking the TLS and DTLS Record Protocols|http://www.isg.rhul.ac.uk/tls/Lucky13.html|target='_blank'] - based on information obtained 2015-12-07
* [#3] - [Lucky Thirteen: Breaking the TLS and DTLS Record Protocols (Detailed)|http://www.isg.rhul.ac.uk/tls/TLStiming.pdf|target='_blank'] - based on information obtained 2015-12-07