At first get familiar with this one https://github.com/grails-plugins/grails-spring-security-core/issues/177
As a work-around I would recommend you below mentioned steps.
In your UrlMappings.groovy
make modification:
"500"(controller: "error", action: "denied")
In your Config.groovy
file override errorPage
property
grails.plugin.springsecurity.adh.errorPage = null
And add action in your controller:
def denied() {
render(view: '/login/denied')
}
This works for me.