DotNetNuke before 4.8.2, during installation or upgrade, does not warn the administrator when the default (1) ValidationKey and (2) DecryptionKey values cannot be modified in the web.config file, which allows remote attackers to bypass intended access restrictions by using the default keys.

Unrestricted file upload vulnerability in the file manager module in DotNetNuke before 4.8.2 allows remote administrators to upload arbitrary files and gain privileges to the server via unspecified vectors.

Cross-site scripting (XSS) vulnerability in Default.aspx in Perpetual Motion Interactive Systems DotNetNuke before 3.3.5, and 4.x before 4.3.5, allows remote attackers to inject arbitrary HTML via the error parameter.