title: Jenkins allow unsafe plugin
body: <p>I'm setting up a new Jenkins instance on a closed network. I would like for the Jenkins build-server to be able to use the Grails plugin. The plugin however does not show under available plugins. </p>
  
  <p>I think it is because of the following: <a href="https://jenkins.io/security/advisory/2017-04-10/" rel="nofollow noreferrer">https://jenkins.io/security/advisory/2017-04-10/</a> that states that the plugin is unsafe.</p>
  
  <p>Inspecting <a href="http://updates.jenkins-ci.org/update-center.json" rel="nofollow noreferrer">http://updates.jenkins-ci.org/update-center.json</a> shows then plugin, but only in regards to the security warning:</p>
  
  <pre><code>    {
          "id": "SECURITY-458",
          "message": "Arbitrary code execution vulnerability",
          "name": "grails",
          "type": "plugin",
          "url": "https://jenkins.io/security/advisory/2017-04-10/",
          "versions": [
              {
                  "pattern": ".*"
              }
          ]
      }
  </code></pre>
  
  <p>Is there any way to force Jenkins to be able to download and use this plugin?</p>