CVE-2026-86205 h3 before 2.0.1-rc.18 Open Redirect via redirectBack()

h3 versions before 2.0.1-rc.18 contain an open redirect vulnerability in the redirectBack utility that fails to sanitize protocol-relative paths in the Referer header pathname. Attackers can craft a same-origin URL with a double-slash path segment that passes origin validation but produces a...