CVE-2026-57149: plone.app.portlets Vulnerable to Remote Code Execution via TALES Injection
plone.app.portlets.portlets provides a Plone-specific user interface for plone.portlets, as well as a standard set of portlets that ship with Plone. Starting in version 5.0.0 and prior to versions 5.0.8, 6.0.4, and 7.0.2, the Classic portlet (plone.app.portlets.portlets.classic) used its user-supplied template/macro fields to build a TALES path expression that was then evaluated by the TAL path() helper. Because the value was interpreted as a full TALES expression, a user able to add or edit a Classic portlet could supply a crafted value that escapes simple path traversal and is evaluated as arbitrary code. This is exploitable by any authenticated user who can configure a Classic portlet - which, with the default role map, includes regular users on their personal dashboard. The result is code execution in the context of the Plone process, i.e. a privilege escalation across the trust boundary between an authenticated web user and the server-side process. The problem has been patched in plone.app.portlets 5.0.8, 6.0.4, and 7.0.2. Some workarounds are available. Restrict who can manage portlets: remove the plone.app.portlets.ManageOwnPortlets permission from untrusted roles, and limit Manage portlets to trusted administrators (usually this is already restricted to the Manager and Site Administrator roles). Where the Classic portlet is not needed, unregister it so it cannot be added. This would need to be done by editing a portlets.xml in your own code. One may also effectively disable showing the classic portlet by customising its template. In the Zope Management Interface go to the portalviewcustomizations tool, locate the classic.pt template and click it. Click the Customize button. Remove all text and replace it with <div>The classic portlet was disabled.</div>. (This is not a recommended way of customizing a template, but in this case it is quite effective.)
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
plone.app.portletsto a version that resolves this vulnerability.Fixed in 5.0.8 - Upgrade
Upgrade
plone.app.portletsto a version that resolves this vulnerability.Fixed in 6.0.4 - Upgrade
Upgrade
plone.app.portletsto a version that resolves this vulnerability.Fixed in 7.0.2 - Configuration
In the Zope Management Interface, customize portal_view_customizations/classic.pt by replacing all text with <div>The classic portlet was disabled.</div>.
Classic portlet template (classic.pt) template content = <div>The classic portlet was disabled.</div> - Configuration
Remove the plone.app.portlets.ManageOwnPortlets permission from untrusted roles and limit Manage portlets to trusted administrators, usually Manager and Site Administrator roles.
Plone portlet management permissions plone.app.portlets.ManageOwnPortlets and Manage portlets access = Remove ManageOwnPortlets from untrusted roles and restrict Manage portlets to trusted administrators - Configuration
Where the Classic portlet is not needed, unregister it so it cannot be added.
Classic portlet (plone.app.portlets.portlets.classic) portlet registration = unregistered
Event History
Frequently Asked Questions
Who can exploit this in a default Plone deployment?
Any authenticated user who can configure a Classic portlet can exploit it. With the default role map, this includes regular users configuring portlets on their personal dashboard.
What access does an attacker need?
The attacker needs an authenticated account and permission to add or edit a Classic portlet. No user interaction is required after the attacker submits the crafted template or macro field value.
What is the impact if exploitation succeeds?
A crafted Classic portlet field can be evaluated as arbitrary code in the Plone process. This crosses the boundary between an authenticated web user and the server-side process, enabling code execution with the process's privileges.
What can be done if updating is not immediately possible?
Restrict portlet-management access by removing the plone.app.portlets.ManageOwnPortlets permission from untrusted roles. This prevents those roles from configuring their own portlets and removes the described default-user exposure.
Which releases contain the fix?
The issue is patched in plone.app.portlets versions 5.0.8, 6.0.4, and 7.0.2. Affected release lines begin at version 5.0.0 and are vulnerable before their corresponding patched version.