.docx files filtered out by amavis - how to stop this?

[Marko Weber | ZBF via amavis-users]

Am 2014-02-21 17:00, schrieb Noel Jones via amavis-users:
> On 2/21/2014 5:24 AM, Marko Weber | ZBF via amavis-users wrote:
>> 
>> hello list,
>> 
>> .docx files get filtered oout on one of our mailgateways.
>> 
>> Feb 19 17:38:00 mail4 amavis[16906]: (16906-18) Blocked BANNED
>> (.exe,.exe-ms,[trash]/0000.dat) {DiscardedInbound,Quarantined},
>> [xxx.xxxx.xxxx.xx] <user at domian.de> -> <user2 at otherdomain.de>,
>> quarantine: banned-Dv5waHtnLz4F, Message-ID:
>> <OF21DF38A4.21A8799C-ONC1257C84.005B32CC-C1257C84.005B5195 at domain.de>,
>> mail_id: Dv5waHtnLz4F, Hits: -, size: 894942, 637 ms
>> 
>> i can see this: [trash]/0000.dat)
>> in the log entry.
>> 
>> does this mean , the mail is filtered out because MS Outllok adds an
>> .dat in the mail?
>> 
>> and how can i ensure, that .docx are not filtered out?
>> 
>> thank you
>> 
>> 
>> best regards
>> 
>> marko
> 
> 
> The file is recognized as an executable by file(1) -- this doesn't
> have anything to do with the extension, but the contents.
> 
> I get around this by putting near the top of amavisd.conf banned
> file list:
> 
> $banned_filename_re = new_RE(
> 
> # allow trash sections of docx files
>   [ qr'^\[trash\]/[0-9a-f]{4}\.dat$' => 0 ],   # allow
> [trash]hhhh.dat in docx files
> 
> ... other stuff to block files
> 
> 
> There may be a more elegant way, but this works for me.
> 
> 
>   -- Noel Jones

thanks Noel,
this worked for us.

marko