Upcoming Inbound Filtering

Coming soon for mailbaby users is the ability to enable inbound filtering. Like our outbound filtering this will include a real time log, going back 30 days for inbound email. Inbound has been a frequent request and the filtering system has been made based on our long running internal filtering system that has been active for many years. This is far more than a simple filter. We’ve engineered an advanced spam and virus detection engine built on the massive, real-time data stream from our global spamtraps and our analysis of compromised accounts. This unique insight allows us to identify and neutralize new spam campaigns, malware, and phishing attacks the moment they emerge—protecting your inbox before a threat even reaches you.

Powerful, Flexible Filtering

As this is a beta, our initial goal is to provide maximum protection with minimal disruption. By default, our system applies a “tag-and-pass” philosophy for most message, so spam will pass unless it is totally obvious:

Extreme Spam: We will hard-block the most obvious and malicious spam and viruses before they ever consume your resources
Suspicious Mail: Messages that look suspicious are given a high spam score and the **subject line is rewritten** (e.g., [SPAM] Your Subject). This allows you to easily filter these messages on your mail server or in your client, ensuring you don’t miss a potential false positive.
Further data in headers: Headers will include ip, location and asn information of the sender, as well as some spam rules trigged.

We believe in giving you control and this platform already supports highly granular settings. You will have the ability to:

Adjust Aggression: Set custom block and greylisting score levels for your entire account (Mailbaby user).
Create Blocklists: Build custom blocklists that apply to a specific domain, a single email address, or your entire Mailbaby user account.

Onboarding will be easy:

Setting up your domain will be simple, three-step process to route your mail through our filtering service.

Step 1: Enable a domain. There will be a 7 day windows before the pending domain will be removed. To finish it two steps will be neeeded:

Step 2: Update Your MX Record

Point your domain’s MX record to our filtering server:

smtp1.inboundspamprotection.com

Step 2: Add a TXT Verification Record

To prove ownership of your domain, please add the following TXT record to your DNS. This record tells our system that you have authorized us to receive your mail.

_inbound IN TXT “v2=mbusername”

(Replace mbusername with your actual Mailbaby account username.

Whats under the hood

Like outbound filtering, inbound is build once again on FreeBSD systems and Rspamd spam filtering. Onboarding is easy where domain smtp forwarding systems and custom rules store in an in-memory data store. EMail arrives to the inbound filter server, is scanned, scored and forwarded to your smtp server. This service will not forward to a single email but requires being in front on an existing mail server. If your server is offline, the email will be queued and delivered when it is online following standard smtp retries.

This service will be slowly rolled out for users over the next few months. Questions? Just reach out to support.