Spamhaus SBLCSS

I keep having an issue with one of my IPv6 addresses being listed on the SBLCSS. This server only runs NextCloud and a Wordpress website. I've monitored outbound traffic and I haven't seen it send any mail other than daily server emails that get sent to me. The NextCloud site only emails me and the Wordpress site doesn't allow user registration. Any idea why I'd keep getting listed? my IPv4 address doesn't have the same issue.

5 Replies

First off, have you requested a delisting?

Second, note that unlike with ipv4, for ipv6 SBLCSS lists subnets, not individual IP address.

Moreover, SBLCSS is a supplementary list, it is not meant to be used as a [sole] RBL, so you might be looking at someone else's configuration issue.

Unfortunately, I discovered that spamhaus will list IP addresses that have never sent any emails, sometimes they list IP addresses that aren't even assigned to anything. I've had several of my IP addresses listed, from servers that don't even have the capability to send/receive emails. This happens periodically.

This implies that they have some kind of blind listing, either completely random or they use some kind of subnet reputation.

Not much that you can do, just visit their site and request a delisting.

Spamhaus operates several distinct lists, which list for different reasons and mean different things, and the Zen list collates several of them, so be more specific.

I checked my records, in my case the last few listings came from the Spamhaus CSS list (part of the SBL list).

Not fair that they blindly go around listing addresses that have not email capability, or aren't even assigned to a server, poor judgement and implementation on their part.

All my Linode IPv6 addresses (including those that don't send emails) are listed by Spamhaus. I requested delist, but a few days later, it's on the list again.

Google postmaster tool also tells me that my IPv6 address has bad reputation. I don't know why, because I use both IPv6 and IPv4 address and the IPv4 address is in good reputation.

I guess I will no longer use IPv6 to send emails.


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