Mailing List Archive

Disable Links in Body
Hello,

I would like to set up a filter to disable all external links in
received messages.  Can someone point me to where to to start looking
into that type of filtering?

-Patrick

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Re: Disable Links in Body [ In reply to ]
Patrick Porteous via Exim-users <exim-users@exim.org> (Mi 09 Jun 2021 21:58:24 CEST):
> Hello,
>
> I would like to set up a filter to disable all external links in received
> messages.  Can someone point me to where to to start looking into that type
> of filtering?

I wouldn't even think about manipulating the mail body. It is asking for
endless trouble. You won't be able to do it in a perfect way, signatures
will be broken, replies will contain dysfunctional links.

If you want to protect your users, restrict their access to external
resources (e.g. force them to use a proxy under your control).

Best regards from Dresden/Germany
Viele Grüße aus Dresden
Heiko Schlittermann
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Re: Disable Links in Body [ In reply to ]
This can be done using a system or transport filter. There you can pass
the initial message to a script - a handler written, for example, in
Perl or any other language convenient for you.
Be prepared to deal with different types of content, including nested
MIMEs. In addition, this will lead to an error in DKIM verification if
it is performed after changing the message body.

Patrick Porteous via Exim-users ????? 2021-06-09 21:58:
> I would like to set up a filter to disable all external links in
> received messages. Can someone point me to where to to start looking
> into that type of filtering?

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Best regards,
Max Kostikov

W: https://kostikov.co | E: max@kostikov.co | T: +7(952)7927000