An issue in Plone CMS v. 5.2.4, 5.2.3, 5.2.2, 5.2.1, 5.2.0, 5.1rc2, 5.1rc1, 5.1b4, 5.1b3, 5.1b2, 5.1a2, 5.1a1, 5.1.7, 5.1.6, 5.1.5, 5.1.4, 5.1.2, 5.1.1 5.1, 5.0rc3, 5.0rc2, 5.0rc1, 5.0.9, 5.0.8, 5.0.7, 5.0.6, 5.0.5, 5.0.4, 5.0.3, 5.0.2, 5.0.10, 5.0.1, 5.0, 4.3.9, 4.3.8, 4.3.7, 4.3.6, 4.3.5, 4.3.4, 4.3.3, 4.3.20, 4 allows attacker to access sensitive information via the RSS feed protlet.