Sudden dropoff in volume of spam

[Michael St. Laurent]

David Hooton <mailto:david at PLATFORMHOSTING.COM> wrote:
>> I've noticed a relatively sudden reduction in the amount of spam
>> being received by our company this week.  Has anyone else noticed
>> this trend?
>
> We've seen 3 changes:
> 1) Some customers have had an approximate 40% reduction in spam
> arriving for filtering, but not all.

Yep.  Actually at our site it seems more like a 75% dropoff.

> 2) The percentage of spam that was identified as high scoring has
> risen by an additional 15% or so

Yep again.  I'd say at least 75% of the spam we're getting is being
categorized as High Scoring.  Part of this may be that I bumped the BAYES_99
score up to 8.000

> 3) An increasingly high percentage of spam received over the last few
> weeks is from trojaned machines.

Interesting.  How can you tell?

> We've recently started using dynamic range blocks on SMTP connect
> which is why I suspect we're seeing what we are.

Cool!  How are you doing that?  iptables?  hosts.deny?

Thanks for responding Dave.

--
Michael St. Laurent
Hartwell Corporation