Data Center operations mail list?

Fri Aug 14 19:16:15 UTC 2015

On Wed, Aug 12, 2015 at 8:36 PM, Phill Twiss <phill at daa.com.au> wrote:
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> De-lurking
>
> Hi Rafael and everyone else :}( sorry the cross-post )
>
>         You should really have captcha's configured for your mailman lists
>
>         Some shady actors out there are using mailman lists to target certain
> email addresses.  Its a pretty dumb attack, but its annoying :}
>
>         The target will be hit by hundreds ( if not thousands ) of subscribe
> confirmation requests.
>
>         We changed to captcha's a month or more ago, we still get an average
> of 300 od IP's trying to do this in period of a few hours.
>
>         Keep an eye out in your logfiles for some of the strings below ( they
> all seem to try to use the same password ), if you have any issues
> with getting captcha's to work properly, drop me an email :}
>
>         Below is an sanitised ( list name and target) entry from the Apache
> logs ( the IP is real, screw em :} )
>
> 64.234.104.150 - - [13/Aug/2015:08:15:54 +0800] "GET
> /mailman/subscribe/<<Sanitised list name >>?email=<< Sanitised_TARGET
>>> @YAHOO.COM&fullname=&pw=123456789&pw-conf=123456789&language=en&diges
> t=0&email-button=Subscribe
> HTTP/1.1"
>>>
> 301 801 "http://tools.vietche.biz/Boom/" "Mozilla/5.0
> (Windows NT 6.1; WOW64; rv:39.0) Gecko/20100101 Firefox/39.0"

That's a very old (in Internet Years) Mailman problem that was solved
with session cookies in v2.1.16 (16-Oct-2013).  If you're still
paranoid, and don't want to piss your users off with privacy leaking
captcha, then just set up some referer checking in your apache or
nginx configs:

Apache:

      # Prevent subscription request spam
     SetEnvIf Referer lists\.example\.com localreferer
     <Location /mailman/subscribe>
        Order deny,allow
        Deny from all
        Allow from env=localreferer
     </Location>

Nginx:

        location /mailman/subscribe {
                valid_referers server_names;
                if ($invalid_referer) { return 403; }
        }

-Jim P.