SSLEngine.unwrap fails with ArrayIndexOutOfBoundsException

The following stack trace was reported while testing WebLogic Server with JDK 9 (seems to be jdk-9+149).

java.lang.ArrayIndexOutOfBoundsException: 50
  at
java.base/sun.security.ssl.InputRecord.convertToClientHello(InputRecord.java:3
47)
  at
java.base/sun.security.ssl.SSLEngineInputRecord.handleUnknownRecord(SSLEngineI
nputRecord.java:391)
  at
java.base/sun.security.ssl.SSLEngineInputRecord.decode(SSLEngineInputRecord.ja
va:195)
  at
java.base/sun.security.ssl.SSLEngineImpl.readRecord(SSLEngineImpl.java:968)
  at
java.base/sun.security.ssl.SSLEngineImpl.readNetRecord(SSLEngineImpl.java:895)
.
  at java.base/sun.security.ssl.SSLEngineImpl.unwrap(SSLEngineImpl.java:673)
  at java.base/javax.net.ssl.SSLEngine.unwrap(SSLEngine.java:664)
  at
weblogic.security.SSL.jsseadapter.JaSSLEngine$5.run(JaSSLEngine.java:135)