This was fixed a week before this article was written: https://symfony.com/blog/cve-2021-41267-webcache-poisoning-via-x-forwarded-prefix-and-sub-request https:

This was fixed a week before this article was written: https://symfony.com/blog/cve-2021-41267-webcache-poisoning-via-x-forwarded-prefix-and-sub-request https://symfony.com/blog/cve-2021-41267-webcache-poisoning-v...