Products.isurlinportal is a replacement for isURLInPortal method in Plone. Versions of Products.isurlinportal prior to 1.2.0 have an Open Redirect vulnerability. Various parts of Plone use the 'is url in portal' check for security, mostly to see if it is safe to redirect to a url. A url like `https://example.org` is not in the portal. The url `https:example.org` without slashes is considered to be in the portal. When redirecting, some browsers go to `https://example.org`, others give an error. Attackers may use this to redirect victims to their site, especially as part of a phishing attack. The problem has been patched in Products.isurlinportal 1.2.0.

In Plone 5.0 through 5.2.4, Editors are vulnerable to XSS in the folder contents view, if a Contributor has created a folder with a SCRIPT tag in the description field.

Zope Products.CMFCore before 2.5.1 and Products.PluggableAuthService before 2.6.2, as used in Plone through 5.2.4 and other products, allow Reflected XSS.

Plone through 5.2.4 allows XSS via the inline_diff methods in Products.CMFDiffTool.

Plone through 5.2.4 allows remote authenticated managers to conduct SSRF attacks via an event ical URL, to read one line of a file.

Plone through 5.2.4 allows XSS via a full name that is mishandled during rendering of the ownership tab of a content item.

Plone through 5.2.4 allows remote authenticated managers to perform disk I/O via crafted keyword arguments to the ReStructuredText transform in a Python script.

Plone through 5.2.4 allows stored XSS attacks (by a Contributor) by uploading an SVG or HTML document.

Plone though 5.2.4 allows SSRF via the lxml parser. This affects Diazo themes, Dexterity TTW schemas, and modeleditors in plone.app.theming, plone.app.dexterity, and plone.supermodel.

Zope is an open-source web application server. In Zope versions prior to 4.6 and 5.2, users can access untrusted modules indirectly through Python modules that are available for direct use. By default, only users with the Manager role can add or edit Zope Page Templates through the web, but sites that allow untrusted users to add/edit Zope Page Templates through the web are at risk from this vulnerability. The problem has been fixed in Zope 5.2 and 4.6. As a workaround, a site administrator can restrict adding/editing Zope Page Templates through the web using the standard Zope user/role permission mechanisms. Untrusted users should not be assigned the Zope Manager role and adding/editing Zope Page Templates through the web should be restricted to trusted users only.