Authorization header leak on port redirect in mechanize

Summary

Mechanize (rubygem) < v2.8.5 leaks the Authorization header after a
redirect to a different port on the same site.

Mitigation

Upgrade to Mechanize v2.8.5 or later.

Notes

See https://curl.se/docs/CVE-2022-27776.html for a similar vulnerability in curl.

Cookies are shared with a server at a different port on the same site, per
https://datatracker.ietf.org/doc/html/rfc6265#section-8.5 which states in part:

> Cookies do not provide isolation by port. If a cookie is readable
> by a service running on one port, the cookie is also readable by a
> service running on another port of the same server. If a cookie is
> writable by a service on one port, the cookie is also writable by a
> service running on another port of the same server. For this
> reason, servers SHOULD NOT both run mutually distrusting services on
> different ports of the same host and use cookies to store security-
> sensitive information.