I was formerly the 'spam janitor' with the job of reviewing and publishing the spam submissions. Although the antispam central blacklist is still running it is indeed hardly ever updated now. There are two reasons for this.
1) The recent versions of b2evo don't seem to interact with the blacklist in the same way, and for whatever reason the number of submissions to the blacklist is lower than it used to be.
2) Spam is getting cleverer and our way of identifying spam which dates back many years is not as good as it used to be - in fact, it's pretty poor nowadays. Obviously I'm not going into the detail of what criteria we use to detect spam but suffice to say it isn't flexible enough to respond to the fast-changing tends in comment spam.

The developers are aware of this issue and as a result there is likely to be a review of the antispam system in a future release. In the meanwhile the existing system still has a good hit rate for quite a lot of traditional spam, so do keep using it, but updates are likely to be few if any until the system is reviewed.

Thanks @filthio for the heads up.

Just for the records, this is the current update timestamp of the antispam central blacklist:

New latest update timestamp: 2014-02-24 21:10:18

Regards!

Yes, I went in and had a quick go :)

I have a document with some more detailed observations which I'd be happy to share with any suitable person who wants to have a go at the antispam development. FP has seen a version of this already.

@filthio I have sent your doc to @mgsolipa already ;)

So you guys are working on it? Lately I have experienced several scheduled task errors from 3 different b2evolution 6.7.3 instances, of the form:

-------------BEGIN-----------------------
Requesting lock on task #418 [Poll the antispam blacklist]

Starting task #418 [Poll the antispam blacklist] at 22:05:21.

Task finished at 22:05:22 with status: error
Message: [Error code: 100 ] Latest update timestamp: 2014-02-24 21:10:18
Requesting abuse list from antispam.b2evo.net...
Remote error: Didn't receive 200 OK from remote server. (HTTP/1.1 500 Internal Server Error) (5)
--------------------END---------------

Best Professional Regards.

Yes, the server died big time last week. We are working on a new system. It is not critically urgent. Expect approx 10 days before fix.

Aha! This explains the email messages I have been receiving. I'll check back to see what progress in a few days.

This is still item #3 on our TODO list and keeps getting passed by more urgent bugs.

Quick update: we are making some progress on this.

We have a new system that will allow anyone to run a central antispam blacklist if they wish to (so you don't have to be dependent on us for updates if you don't want to).

We are also currently reconstructing the full central list and we are augmenting it with some additional strings.

OK, so the antispam server is back up now, and with some additional blacklist strings to serve.

Your system should be able to continue polling without any action on your part.

Please let us know if anything looks wrong.

Also please feel free to start reporting strings again. We have a better system to moderate them now ;)

@fplanque wrote earlier:

Quick update: we are making some progress on this.

We have a new system that will allow anyone to run a central antispam blacklist if they wish to (so you don't have to be dependent on us for updates if you don't want to).

Noticing the latest antispam blacklist timestamp and the status of b2evolution as effectively orphaned, I checked the b2evo manuals hosted at this site and have not found an update on the 'Quick update... allowing anyone to run a central antispam blacklist if they so wish...'

Fact is, if your server(s) get hacked due to lack of diligence applying updates to an already orphaned PHP App, any of the remaining third-parties' b2evo instances out there who poll the central antispam blacklist may potentially get malware in return.

That is, I disabled the antispam blacklist polling job precisely because I am encountering:

The following scheduled task has ended with an error:

Poll the antispam blacklist (#abcdxy):
Error code: 100
Result message: Latest update timestamp: 2020-07-16 14:22:50
Requesting abuse list from antispam.b2evo.net...

Manually triggering the polling of the antispam blacklist is refused.