Summary

Remove TLS cipher suites that use 3DES from the default list of enabled cipher suites supported by the SunJSSE provider.

Note that cipher suites using 3DES are already disabled by default in the jdk.tls.disabledAlgorithms security property. This change would go one step further and make them unavailable by default, even if removed from the jdk.tls.disabledAlgorithms security property.

Problem

Cipher suites using 3DES are weak and vulnerable to known attacks such as Sweet32 and should not be used in practice anymore. Per RFC 7525, implementations SHOULD NOT negotiate cipher suites that use algorithms offering less than 128 bits of security. The strength of 3DES is 112 bits, which is less than 128 bits of security.

As noted in the Summary, 3DES suites are already disabled by default via the jdk.tls.disabledAlgorithms security property. This change provides additional defense-in-depth by making them unavailable in the default list at run time. An application that wants to use a 3DES suites will need to remove 3DES from the jdk.tls.disabledAlgorithms security property and explicitly configure the suite using an API such as SSLSocket::setEnabledCipherSuites().

Solution

Remove the following TLS cipher suites that use 3DES from the default list of enabled cipher suites:

• TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA
• TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA
• SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA
• SSL_DHE_DSS_WITH_3DES_EDE_CBC_SHA
• TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA
• TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA
• SSL_RSA_WITH_3DES_EDE_CBC_SHA

These cipher suites are still supported by the SunJSSE provider. However, they will no longer be enabled by default and must be configured in order to be enabled (see the Compatibility Risk section for more details).

Specification

This is an implementation change only. See the Solution section for the proposed changes.