Privilege escalation (PR) from account through XWiki.SchedulerJobSheet

Steps to reproduce:

1. As a user without script or programming rights, edit your user profile with the object editor and add a new object of type XWiki.SchedulerJobClass (search for "Scheduler").
2. In "Job Script", add the following

   {{/code}} {{async async="true" cached="false" context="doc.reference"}}{{groovy}}println("Hello " + "from groovy!"){{/groovy}}{{/async}}

3. Click "Save & View"
4. If the job information isn't already displayed (you should see "Job Name", "Job Description", etc.), append ?sheet=XWiki.SchedulerJobSheet to the URL.

Expected result:

Under "Job script" the text

{{/code}} {{async async="true" cached="false" context="doc.reference"}}{{groovy}}println("Hello " + "from groovy!"){{/groovy}}{{/async}}

is displayed.

Actual result:

Under "Job script", the text

 Hello from groovy!{{/code}}

is displayed.

This shows that a user without script or programming rights has successfully executed a Groovy macro and thus gained programming rights. Therefore, this is a privilege escalation vulnerability from account to programming rights.