[Dovecot] Using Dovecot-auth to return error code 450 (or other 4xx) to Postfix when user is on vacation

[Mark Sapiro]

On 11:59 AM, IVO GELOV (CRM) wrote:
> 
> The limitation of 1 message per week for any unique combination of
> sender/recipient
> does not stop backscatter - because each message can come with a new
> forged FROM address,
> and from different compromised mail servers.
> The spammer does not have control over the body of the auto-replies
> (which is something
> like "I am not at the office, please write to my colleagues"), but it still
> may cause the victims to take some measures.


All true, but the sender in the sender/recipient combination is the
forged From: that ultimately receives the backscatter and the recipient
is your local user who set the vacation autoresponse. If you only have
one or two local users on vacation at a time, any given backscatter
recipient could receive at most one or two backscatter messages per week
regardless of how many compromised servers the spammer sends from. And
this assumes the spam is initially sent to multiple local users on
vacation and gets past your local spam filtering.

I don't know about you, but I have more significant potential
backscatter sources to worry about.

-- 
Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan