Update current logged user password, using grails spring securit core plugin, i got help in this mail list http://grails.1312388.n4.nabble.com/update-current-user-password-in-spring-security-core-plugin-td4655284.html

profileCommand

package com.testing
import grails.plugin.springsecurity.annotation.Secured

class UserController {
  def springSecurityService

  @Secured(['ROLE_ADMIN'])
  def profile(profileCommand cmd) {
   if (request.method == "POST") {
     if (cmd.hasErrors()) {
       flash.message = "Upps something when wrong"
       return
     }

    cmd.updatePassword()

     flash.message = "Password updated :)"
    }
  }
}

//validations in command object
class profileCommand {
  def springSecurityService
  def passwordEncoder

  String password
  String newPassword
  String repeatPassword

  static constraints = {
    password blank: false, validator: { val, obj ->
      def currentUser = obj.springSecurityService.currentUser
      def currentUserPassword = currentUser.password

      return obj.passwordEncoder.isPasswordValid(currentUserPassword, val, null)
    }
    newPassword validator: { val, obj ->
      val == obj.repeatPassword
    }
  }
  
  User updatePassword() {
    User currentUser = springSecurityService.currentUser

    currentUser.password = newPassword

    currentUser.save(flush: true)
  }
}