Kentico CMS in version 7 is vulnerable to a Reflected XSS attacks through manipulation of a specific GET request parameter sent to /CMSMessages/AccessDenied.aspx endpoint. Notably, support for this version of Kentico ended in 2016. Version 8 was tested as well and does not contain this vulnerability.
Multiple cross-site scripting (XSS) vulnerabilities in Kentico CMS 8.2 allow remote attackers to inject arbitrary web script or HTML via a (1) parameter name to CMSModules/AdminControls/Pages/UIPage.aspx or the (2) CMSBodyClass cookie variable to the default URI.
Open redirect vulnerability in CMSPages/GetDocLink.ashx in Kentico CMS 8.2 through 8.2.41 allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via a URL in the link parameter.
The Blog module in Kentico CMS 5.5 R2 build 5.5.3996 allows SQL injection via the tagname parameter.