Viktor Dukhovni: > On Mon, Jun 02, 2014 at 01:15:37PM +0200, Alessandro Vesely wrote: > > > and even a dubious: > > > > Content-Disposition: attachment; > > filename*0*="''attached%2E"; > > filename*1*="%62"; > > filename*2=at > > That's not dubious, that's RFC 2231. The MIME normalizer I wrote > some years back, (sorry not publically available) was able to > recognize restricted file extensions even in this case. > > Sufficiently advanced MIME encodings require more than than a > regular expression matcher to recognize. The attachment filtering > in header_checks is a best-effort junk reduction technique, not a > robust defense.
Postfix documentation states in more than one place that header/body_checks are not and will not be a deep content filter. If that is what you want, then use the right tool for the right job. Wietse