GHSA-q3m9-9fj2-mfwr

### Impact 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. But the url `https:example.org` without slashes tricks our code and it _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 you to their site, especially as part of a phishing attack. ### Patches The problem has been patched in `Products.isurlinportal` 1.2.0. This is a recommended upgrade for all users of Plone 4.3 and 5, on Python 2.7 or higher. It has not been tested on earlier Plone or Python versions. Upcoming Plone 5.2.5 and higher will include the new version. ### Discovered This vulnerability was discovered and reported by Yuji Tounai of Mitsui Bussan Secure Directions, Inc. Thank you! ### For more information If you have any questions or comments about this advisory: * Email the Plone Security Team at [[email protected]](mailto:[email protected]), especially when you think you have discovered a security problem or when you are not sure. * Open an issue in [the tracker](https://github.com/plone/Products.isurlinportal/issues) if your question or comment can be public.