RE: [exim] blocking executable attachments

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Author: Herb Martin
Date:  
To: exim-users
Subject: RE: [exim] blocking executable attachments
> ---
> deny message = Attachments of type ".$found_extension" not
> allowed demime = bat : cmd : com : exe : lnk : pif : scr
> logwrite = :main,reject: bad atachment ($found_extension).
> ---
>
> This works very well; now I would like to do it the "modern
> way", like:
>
> ---
> deny message = Attachments of type ".$found_extension" not
> allowed condition = ${if match \
> {${lc:$mime_filename}} \
> {\N\.(bat|cmd|com|exe|lnk|pif|scr)$\N} \
> {yes} {no} \
> }
> logwrite = :main,reject: bad atachment ($found_extension).


While you are reviewing this you might wish to consider
a longer list of dangerous extenstions -- most of these
that I use are also disallows by Microsoft Word so many
users would find these unavailable even if they were allowed
to pass the server:

EXECUTABLE_EXTENSIONS_COLON = \
      386 : acm : avb : bin : cla : class : cnv\
     dll : drv : ade : adp : app : asp : bas : bat : \
     cer : chm : cmd : com : cpl : crt : csh : exe : \
     fxp : hlp : hta : inf : ins : isp : its : js  : \
    jse : ksh : lnk : mad : maf : mag : mam : maq : \
    mar : mas : mat : mau : mav : maw : mda : mdb : \
    mde : mdt : mdw : mdz : msc : msi : msp : mst : \
    ops : pcd : pif : prf : prg : pst : reg : scf : \
    scr : sct : shb : shs : tmp : url : vb  : vbe : \
    vbs : vss : vst : vsw : ws  : wsc : wsf : wsh


EXECUTABLE_EXTENSIONS = 386|acm|avb|bin|cla|class|cnv\
    dll|drv|ade|adp|app|asp|bas|bat|\
    cer|chm|cmd|com|cpl|crt|csh|exe|\
    fxp|hlp|hta|inf|ins|isp|its|js|\
    jse|ksh|lnk|mad|maf|mag|mam|maq|\
    mar|mas|mat|mau|mav|maw|mda|mdb|\
    mde|mdt|mdw|mdz|msc|msi|msp|mst|\
    ops|pcd|pif|prf|prg|pst|reg|scf|\
    scr|sct|shb|shs|tmp|url|vb|vbe|\
    vbs|vss|vst|vsw|ws|wsc|wsf|wsh


Herb Martin, MCT, MCSD, MCSE, MVP
HerbM@??? http://LearnQuick.Com
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