.NET Open Redirect Guide: Examples and Prevention

Open redirect vulnerabilities, which occur when a web application redirects users to unvalidated and potentially malicious URLs, are a common yet often overlooked security threat. These vulnerabilities exploit the ubiquity of redirects on the web, which are commonly used to guide users between URLs for functionality and security purposes. Attackers can leverage open redirects in phishing scams to steal credentials by misleading users to malicious websites that appear legitimate due to the presence of the original domain in the URL. Despite the low impact on the platform itself, these vulnerabilities can significantly damage user trust. Prevention strategies include eliminating unnecessary redirects, limiting redirection destinations, employing the "LocalRedirect" helper in .NET to ensure URLs are local, and conducting regular security audits. These measures, while potentially time-consuming, are crucial for maintaining platform security, and tools like StackHawk may offer additional support in managing these vulnerabilities.