Re: SPAMMERS DELIGHT: as feeble as feeble can be

From: Jay D. Dyson (jdysonat_private)
Date: Mon Dec 10 2001 - 20:44:10 PST

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    On Mon, 10 Dec 2001, http-equivat_private wrote:
    
    > Forget about open relays. There is an extremely simple mailto form
    > application called mailto.exe available on the internet. Simply create
    > your html form, upload the mailto.exe into your cgi bin and fire away. 
    
    	This is really just a somewhat new face on an old problem.  A
    similar search for formmail.[pl|cgi] and similar web->mail gateway scripts
    will yield equal -- if not greater -- spam injection vectors.  There's
    loads of those beasties out there, and they can be trivially tricked into
    serving as a spam-spewing machine; usually with no equivalent of the
    common X-Originating-IP header included. 
    
    	Bottom line: just because your server doesn't support the likes of
    mailto.exe on it doesn't mean your boxen aren't vulnerable to this sort of
    net.abuse.  If one's httpd.conf has "AddHandler cgi-script" enabled, and
    allows ExecCGI on personal directories, one's web site can be readily
    exploited for such purposes.  Heck, even the absence of the sendmail
    binary doesn't qualify as a stumbling block since PERL's Net::SMTP can be
    used in its place. 
    
    	All told, if one is going to run a web->mail gateway, it's a good
    idea to have pre-defined destination addresses defined within the CGI and
    well outside the HTML form.  Relying on "hidden" fields and an expectation
    that everyone will play nice in the sandbox is just a recipe for spammer
    mischief these days.
    
    - -Jay
    
       (    (                                                        _______
       ))   ))   .-"There's always time for a good cup of coffee"-.   >====<--.
     C|~~|C|~~| (>----- Jay D. Dyson -- jdysonat_private -----<) |    = |-'
      `--' `--'  `---------- Si vis pacem, para bellum. ----------'  `------'
    
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