[Esd-l] 2 questions about double extension check

John D. Hardin jhardin at impsec.org
Mon Aug 16 20:49:55 PDT 2004

On Mon, 16 Aug 2004, Michael Meltzer wrote:

> Is it possible (an if so how) to restrickt the double extension
> check of the sanitizer to a certain minimum size of the message
> including the attachment ?

Hrm. Well, the double-extension check isn't hardcoded, it's in the
poisoned extensions list, so you could try this:

1) Make two poison lists, one with the all extensions including the
double-extension entries, the other omitting just the
double-extension entries. Then,

2) In your /etc/procmailrc where you set your poison filename, try
something like this:


  * > 200000

(substitute whatever size you want in place of the "200000")

> Is it possible to check double extensions only against the
> extensions in the MANGLE_EXTENSION variable or against an other
> variable or file ?

At the moment only $MANGLE_EXTENSION extensions are checked against
the poisoned filenames list.

 John Hardin KA7OHZ    ICQ#15735746    http://www.impsec.org/~jhardin/
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