CVE-2026-41706: Spring Security: Open Redirect via Unvalidated Post-Login Redirect URL Stored in CookieRequestCache

Spring Security’s CookieRequestCache and CookieServerRequestCache store the pre-authentication request URL in a browser cookie so that users can be redirected back to their intended destination after a successful login. In affected versions, the full absolute URL is stored in the cookie and is used without validation as the post-login redirect target.

Affected versions: Spring Security 5.7.0 through 5.7.23; 5.8.0 through 5.8.25; 6.3.0 through 6.3.16; 6.4.0 through 6.4.16; 6.5.0 through 6.5.10; 7.0.0 through 7.0.5.