3155527 – Update to Cipher Suites for FalseStart – Version: 1.0

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Revision Note: V1.0 (May 10, 2016): Advisory published.
Summary: FalseStart allows the TLS client to send application data before receiving and verifying the server Finished message. This allows an attacker to launch a man-in-the-middle (MiTM) attack to force the TLS client to encrypt the first flight of application_data records using the attacker’s chosen cipher suite from the client’s list. To avoid downgrade attacks, TLS clients only allow FalseStart when their strongest cipher suites are negotiated.