GHSA-vgxm-h9gx-h9w7: Medium severity pip/django-cms vulnerability
Summary The structure-board endpoint (renderobjectstructure) renders a page's plugin structure without verifying that the requesting user is allowed to view the page. The edit and preview endpoints enforce this via renderpage(), but the structure endpoint does not, allowing a low-privileged staff user to read the plugin structure of a view-restricted page.
Details renderobjectstructure (in cms/views.py) loads the PageContent object and renders cms/toolbar/structure.html directly. Unlike renderobjectendpoint (used by edit/preview), which renders through renderpagecontent → renderpage and calls usercanviewpage(request.user, page) (returning 404 when the user may not view the page), the structure endpoint performs no page-level authorization.
The rendered structure board includes each plugin's getshortdescription() (e.g. link names/URLs, text snippets), so the content of a restricted page is disclosed, not just its shape.
Impact A staff user (any account with isstaff=True) who lacks view permission on a view-restricted page can retrieve that page's plugin structure and short descriptions by requesting the structure endpoint with the page's content-type id and object id.
This only applies when CMSPERMISSION=True and the page has view restrictions (or CMSPUBLICFOR='staff'). Sites without per-page view restrictions are not affected.
Patches Fixed in 5.0.8: the structure endpoint now enforces usercanviewpage() for PageContent objects, matching edit/preview.
Workarounds None other than restricting staff access. Upgrade is recommended.
Credits Reported by the security team at the University of Sydney ([@reporter]).
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
pip/django-cmsto a version that resolves this vulnerability.Fixed in 5.0.8 - Upgrade
Upgrade
5.0.8to a version that resolves this vulnerability.Fixed in 5.0.8 - Compensating control
Restrict staff access (any account with `is_staff=True`) to the structure endpoint so that staff users cannot request `render_object_structure` for view-restricted `PageContent` objects.
Event History
Frequently Asked Questions
Who can exploit this issue?
An authenticated account with is_staff=True can exploit it if the account does not have permission to view a view-restricted page. The issue is reachable over the network and does not require user interaction.
What information can be disclosed?
The structure endpoint exposes the page's plugin structure and each plugin's short description. Depending on the plugins used, this can disclose link names and URLs, text snippets, and other restricted page content represented in plugin descriptions.
Are edit and preview endpoints affected in the same way?
No. The edit and preview paths render through render_page(), which checks whether the user can view the page and returns a 404 when they cannot. The missing page-level authorization check is specific to the structure-board endpoint described.
How can an administrator determine whether access may have been exposed?
Review whether staff accounts exist that lack view permission for restricted pages, since any such account could request those pages' structure endpoint. Pages whose plugins contain sensitive short descriptions are the most relevant exposure candidates.