Kentico 11 through 12 lets attackers upload and explore files without authentication via the cmsmodules/medialibrary/formcontrols/liveselectors/insertimageormedia/tabs_media.aspx URI. NOTE: The vendor disputes the report because the researcher did not configure the media library permissions correctly. The vendor states that by default all users can read/modify/upload files, and it’s up to the administrator to decide who should have access to the media library and set the permissions accordingly. See the vendor documentation in the references for more information

An issue was discovered in Kentico 12.0.x before 12.0.15, 11.0.x before 11.0.48, 10.0.x before 10.0.52, and 9.x versions. Due to a failure to validate security headers, it was possible for a specially crafted request to the staging service to bypass the initial authentication and proceed to deserialize user-controlled .NET object input. This deserialization then led to unauthenticated remote code execution on the server where the Kentico instance was hosted.

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.

In Kentico before 13.0.66, attackers can achieve Denial of Service via a crafted request to the GetResource handler.

Kentico CMS before 13.0.66 has an Insecure Direct Object Reference vulnerability. It allows an attacker with user management rights (default is Administrator) to export the user options of any user, even ones with higher privileges (like Global Administrators) than the current user. The exported XML contains every option of the exported user (even the hashed password).

The Kentico Xperience CMS version 13.0 – 13.0.43 is vulnerable to a persistent Cross-Site Scripting (XSS) vulnerability (also known as Stored or Second-Order XSS). Persistent XSS vulnerabilities occur when the application stores and retrieves client supplied data without proper handling of dangerous content. This type of XSS vulnerability is exploited by submitting malicious script content to the application which is then retrieved and executed by other application users. The attacker could exploit this to conduct a range of attacks against users of the affected application such as session hijacking, account take over and accessing sensitive data.

The Blog module in Kentico CMS 5.5 R2 build 5.5.3996 allows SQL injection via the tagname parameter.

Cross Site Scripting (XSS) vulnerability in Kentico before 12.0.75.

Kentico before 12.0.50 allows file uploads in which the Content-Type header is inconsistent with the file extension, leading to XSS.

Kentico CMS before 11.0.45 allows unrestricted upload of a file with a dangerous type.