IllegalStateException when provisioning cluster via blueprint during password validation

After submitting cluster create with a default password as well as some passwords specified in BP, a 500 response is returned to the user as a result of an IllegalStateException during password validation.
13:55:48,112 ERROR qtp752317744-20 BaseManagementHandler:62 - Caught a runtime exception while attempting to create a resource
java.lang.IllegalStateException
at java.util.HashMap$HashIterator.remove(HashMap.java:942)
at org.apache.ambari.server.controller.internal.ClusterResourceProvider.validatePasswordProperties(ClusterResourceProvider.java:379)
at org.apache.ambari.server.controller.internal.ClusterResourceProvider.processBlueprintCreate(ClusterResourceProvider.java:333)
at org.apache.ambari.server.controller.internal.ClusterResourceProvider.createResources(ClusterResourceProvider.java:148)
at org.apache.ambari.server.controller.internal.ClusterControllerImpl.createResources(ClusterControllerImpl.java:218)
at org.apache.ambari.server.api.services.persistence.PersistenceManagerImpl.create(PersistenceManagerImpl.java:75)
at org.apache.ambari.server.api.handlers.CreateHandler.persist(CreateHandler.java:36)
at org.apache.ambari.server.api.handlers.BaseManagementHandler.handleRequest(BaseManagementHandler.java:72)
at org.apache.ambari.server.api.services.BaseRequest.process(BaseRequest.java:126)
at org.apache.ambari.server.api.services.BaseService.handleRequest(BaseService.java:80)
at org.apache.ambari.server.api.services.ClusterService.createCluster(ClusterService.java:82)