DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. A bypass has been identified for the previously known vulnerability CVE-2017-0929, allowing unauthenticated attackers to execute arbitrary GET requests against target systems, including internal or adjacent networks. This vulnerability facilitates a semi-blind SSRF attack, allowing attackers to make the target server send requests to internal or external URLs without viewing the full responses. Potential impacts include internal network reconnaissance, bypassing firewalls. This vulnerability is fixed in 9.13.8.