Does anyone recognise this?

[si...@yacc.co.uk]

Hi,

A happy new year to you all.

I'm seeing a lot of spam containing the following pattern of headers:

X-MimeOLE: Produced by SwiftMailer 3.3.1_4
X-mid: What looks like a message ID=
X-Mailer: AC Mailer

The thing that first got my attention was the SwiftMailer version, which
is pretty old.

I've discovered the X-MimeOLE and X-Mailer components used in a rule
posted in one of the Spamassassin sandbox areas, but not all three
together. Only time I ever see the X-mid header is in connection with
the other two, so maybe omission from the rule represents some kind of
optimisation effort ... I don't know.

Regardless ... this kinda suggests that I'm not the only one being
hassled with this stuff.

Does anyone happen to know what mailer/tool generates this particular
sequence? My first thought was activecampaign (www.activecampaign.com),
but I'm seeing inbound IPs from all over the place, so maybe not.

Thanks for your time & All the BEst

Mup.