Impact

Any user with edit rights can execute arbitrary Groovy, Python or Velocity code in XWiki leading to full access to the XWiki installation. The root cause is improper escaping of the included pages in the IncludedDocuments panel.

Precondition: As an admin, add the Panels.IncludedDocuments panel on one column.

A proof of concept exploit is to edit a document and add the following code before saving.

{{display reference="{{cache~}~}{{groovy~}~}println(~"Hello from Groovy~" + ~" in included document!~"){{/groovy~}~}{{/cache~}~}"/}}

expected
The right had side panels contain:

One included page: 
{{cache}}{{groovy}}println("Hello from Groovy" + " in included document!"){{/groovy}}{{/cache}}

actual
The right had side panels contain:

One included page:
    XWiki.Hello from Groovy in included document!

Patches

The problem has been patched on XWiki 14.4.7, and 14.10.

Workarounds

The issue can be fixed manually applying this patch.

References

• 50b4d91
• https://jira.xwiki.org/browse/XWIKI-20306

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