XWiki Platform privilege escalation from script right to programming right through title displayer

Impact

In XWiki Platform, it's possible for a user to write a script in which any velocity content is executed with the right of any other document content author.

To reproduce:

As a user with script but not programming right, create a document with the following content:

{{velocity}}
#set($main = $xwiki.getDocument('AppWithinMinutes.DynamicMessageTool'))
$main.setTitle('$doc.getDocument().getContentAuthor()')
$main.getPlainTitle()
{{/velocity}}

Since this API require programming right and the user does not have it, the expected result is $doc.document.authors.contentAuthor (not executed script), unfortunately with the security vulnerability we get XWiki.superadmin which shows that the title was executed with the right of the unmodified document.

Patches

This has been patched in XWiki 14.10.7 and 15.2-RC-1.

Workarounds

There are no known workarounds for it.

References

• https://jira.xwiki.org/browse/XWIKI-20624
• https://github.com/xwiki/xwiki-platform/commit/11a9170dfe63e59f4066db67f84dbfce4ed619c6
• https://jira.xwiki.org/browse/XWIKI-20625
• https://github.com/xwiki/xwiki-platform/commit/41d7dca2d30084966ca6a7ee537f39ee8354a7e3

For more information

If you have any questions or comments about this advisory:

• Open an issue in Jira XWiki.org
• Email us at Security Mailing List