During the initial setup of a Transport Layer Security (TLS) connection to the application server, the client sends a list of supported cipher suites in order of preference. The application server will reply with the cipher suite it will use for communication from the client list. If an attacker can intercept the submission of cipher suites to the application server and place, as the preferred cipher suite, a weak export suite, the encryption used for the session becomes easy for the attacker to break, often within minutes to hours. |