CVE-2025-69206: hemmelig allows SSRF Filter bypass via Secret Request functionality

A Server-Side Request Forgery (SSRF) filter bypass vulnerability exists in the webhook URL validation of the Secret Requests feature. The application attempts to block internal/private IP addresses but can be bypassed using DNS rebinding (e.g., localtest.me which resolves to 127.0.0.1) or open redirect services (e.g., httpbin.org/redirect-to). This allows an authenticated user to make the server initiate HTTP requests to internal network resources.