By default, WS SSL will use the most secure version of the TLS protocol available in the JVM. On JDK 1.7 and later, the default protocol is “TLSv1.2”.
The full protocol list in JSSE is available in the Standard Algorithm Name Documentation.
If you want to define a different default protocol, you can set it specifically in the client:
# Passed into SSLContext.getInstance() ssl-config.protocol = "TLSv1.2"
If you want to define the list of enabled protocols, you can do so explicitly:
# passed into sslContext.getDefaultParameters().setEnabledProtocols() ssl-config.enabledProtocols = [ "TLSv1.2", "TLSv1.1", "TLSv1" ]
If you are on JDK 1.8, you can also set the
jdk.tls.client.protocols system property to enable client protocols globally.
WS recognizes “SSLv3”, “SSLv2” and “SSLv2Hello” as weak protocols with a number of security issues, and will throw an exception if they are in the
ssl-config.enabledProtocols list. Virtually all servers support
TLSv1, so there is no advantage in using these older protocols.