eMail Routing is allowing spam to be sent from my domain name

eMail Routing is working fine, all email is being forwarded on to my mailboxes, however it is allowing messages to be sent from ‘me’ to ‘me’ SPF and DKIM passes, DMARC fails.

For Routing to work SPF has to include include:_spf.mx.cloudflare.net

mail is appearing to originate from the cloudflare SMTP server

mail header:
Received-SPF: pass (google.com: domain of [email protected] designates 104.30.8.154 as permitted sender) client-ip=104.30.8.154;

IP address: 104.30.8.154
hostname: i-bfe.email.cloudflare.net
ISP: CLOUDFLARENET

Is there anything that can be done to stop this? the cloudflare SMTP servers are listed as open relays.

Set a DMARC policy on your domain holding “v=DMARC1; p=reject; sp=reject; np=reject;”.

It will be the most strictest DMARC policy you can have, and it would mean that all messages that the Cloudflare Email Routing receives, which is claiming to be from your domain name, but cannot be verified to be so, will then be rejected by the Email Routing.

Note: Unless all of your existing, but legitimate outbound email streams do proper domain authentication (e.g. either DKIM or SPF, including perfect alignment), a such REJECT policy might also mean other destinations are rejecting the messages that you send towards them, if your own messages fails to comply with your new policy.

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