* venerdì 19 settembre 2003, alle 23:08, Guido Bolognesi [ Zen ] scrive:
> La soluzione personale e` da tempo quella di filtrare gli
> attachment "nocivi" (.exe, .com, .scr...) direttamente a livello
> di smtp, cosi` non devo neanche controllare che sia spam. In
> piu` educa gli utenti, eheh.
>
> in main.cf
> header_checks = regexp:/etc/postfix/header_checks
>
> il file header_checks contiene righe tipo
> /Content.*\.vbs/ REJECT vbs not allowed.
Yep. Il vero problema di questa soluzione e`:
- non va bene per chi prende la posta con fetchmail (oddio, va bene, nel
senso che non la riceve, eppero`...)
- ho amplifichi molto bene le regex, ho sei destinato a farne scappare
tanti, tra: vari tipi di cazzi da filtrare, multipart malformati (non
su una riga... c'e` un *splendido* <g> client di posta che lo fa..) e
roba cosi`.
Ragion per cui, piu` che usare header_checks, consiglio e uso
sanitizer.
Description: The Anomy Mail Sanitizer - an email virus scanner
The Anomy sanitizer is what most people would call "an email virus
scanner".
That description is not totally accurate, but it does cover one of the
more
important jobs that the sanitizer can do for you - it can scan email
attachments for viruses. Other things it can do:
.
Disable potentially dangerous HTML code, such as javascript, within
incoming email.
.
Protect you from email-based break-in attempts which exploit bugs in
common email programs (Outlook, Eudora, Pine, ...).
.
Block or "mangle" attachments based on their file names. This way if
you
don't *need* to receive e.g. visual basic scripts, then you don't have
to
worry about the security risk they imply (the ILOVEYOU virus was a
visual basic program). This lets you protect yourself and your users
from whole classes of attacks, without relying on complex, resource
intensive and outdated virus scanning solutions.
--
Maurizio - Tannoiser - Lemmo
Founder Member of ERLUG http://erlug.linux.it
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"How can I tell that the past isn't a fiction designed to account for
the discrepancy between my immediate physical sensations and my state
of mind?" - RAEU
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