The mailing list for listmasters using Sympa

[François Poulain <address@concealed>]

Hi,

On our wwsympa we are getting numerous web requests like
POST /wws/subscribe/listname
from numerous output servers, with numerous emails to be subscribed.

Since we use auth scenario, confirmation email are sent to the
recipients posted.

Each days we send hundreds emails which are blocked by Google (error
450-4.2.1 The user you are trying to contact is receiving mail at a
rate that 450-4.2.1 prevents additional messages from being delivered).

There is no evidence regarding host/ip_addr or email addr which allow
to easily thrash theses subscribe requests.

How do you mitigate with this? Is there a way to add tokens in the
webforms in order to prevent (or at least increase cost of) this
kind of massive spam?

Best regards.
François

-- 
François Poulain <address@concealed>