Hi. Is it possible to downscore mails from a specific mailserver? I have hostname and ip, but I don't just want to make a Received-Header rule to downscore it, because the received header can't be trusted.
I use amavisd-new and postfix on my mailserver to call spamassassin, so spamassassin should be able to get the real IP address from the connecting server to softscore the mail based on this IP. But I have no idea how to do this. Basically my problem is the following: TheCompany is a business partner of ours but we get lots of spam mail that claims to be from TheCompany. So sometimes a correct mail gets caught up in my spamfilter because spamassassin has a hard time to distinguish between real mails from TheCompany and fake spam mails that only claim to be from TheCompany. I know dkim and Co would solve this problem, but I can't do anything on my end. So I want to downscore mails from their specific Mailserver. Is this somehow possible without entirely relying on fakable email headers? Thanks.
