mod_pagespeed exploit? random folders in /var/cache/mod_pagespeed/v3

[sub scriibe]

Hi I created a new DigitalOcean droplet (wordpress one-click install) and then installed mod_pagespeed.

A couple hours later I look in the cache folder /var/cache/mod_pagespeed/ and there are domains getting added there that aren't mine -

    /var/cache/mod_pagespeed/v3/big-events.co.uk
    /var/cache/mod_pagespeed/v3/youexel.com

I am only using this droplet for 1 website so why are all these other websites appearing in the cache?

I found this stackoverflow post with similar problem and I tried to implement the solutions suggested -
https://stackoverflow.com/questions/12724705/strange-domains-in-mod-pagespeed-cache-folder

Please can someone confirm I've added the suggestions correctly?

Suggestion 1 ModPagespeedDomain

I've added this to my .htaccess file -

    <IfModule pagespeed_module>
        ModPagespeed on
        ModPagespeedDomain demo.mywebsite.com
        ModPagespeedMapRewriteDomain demo.mywebsite.com *mywebsite.com
    </IfModule>

Suggestion 2 UseCanonicalName & UseCanonicalPhysicalPort

I added these lines to /etc/apache2/sites-enabled/000-default-le-ssl.conf

    UseCanonicalName On
    UseCanonicalPhysicalPort On

Is there anything I can do to stop this exploit?

Thanks for any help!

[Otto van der Schaaf]

See https://groups.google.com/g/mod-pagespeed-discuss/c/zWgCfnAQIkE/m/lt3ts2IxrssJ

Otto