Securing Apache against mod_proxy SSRF exploit CVE-2021-40438

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I'm tasked with securing Apache against CVE-2021-40438 in order to achieve PCI compliance. The server is running Apache 2.4.52 and PHP-FPM 7.4.26, each running in their own docker container. From what I've read, the version of Apache that I'm using has been patched against this issue, however, I think I'm re-introducing the problem with my need to configure Apache as a proxy for php-fpm.

The relevant configuration options I'm using in the VirtualHost block are below:

ProxyRequests Off
ProxyPassMatch ^/(.*\.php(/.*)?)$ fcgi://php:9000/var/www/html/content/$1

The advice I've found online is simply to disable the proxy_module, but I need it to direct requests to php-fpm. How might I secure my server properly while allowing Apache to act as a proxy for php-fpm. Sorry if this is trivial, I'm inexperienced.


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