CVE-2026-45310: DeepSeek TUI has SSRF via HTTP Redirect Bypass in fetch_url Tool

The fetch_url tool validates the initial URL’s resolved IP address against a restricted-IP blocklist (is_restricted_ip()) to prevent SSRF attacks against internal services (cloud metadata endpoints, localhost, private networks). However, the HTTP client (reqwest) is configured to automatically follow up to 5 redirects (reqwest::redirect::Policy::limited(5)) without re-validating the redirect target against the same SSRF protections.