Researchers at the Royal Holloway University of London have uncovered a range of methods to attack the TLS cryptographic protocol to expose encrypted data circulating between clients and servers. Exploit of the protocol requires that the attacker be close to the target machine to detect small differences in the time at which TLS error messages appear on the network in response to attacker-generated cipher-text messages. The attacks can reliably recover a complete block of TLS-encrypted plaintext using about 223 TLS sessions, assuming the attacker is located on the same LAN.”]