[41387] in bugtraq
Re: - Cisco IOS HTTP Server code injection/execution vulnerability-
daemon@ATHENA.MIT.EDU (Florian Weimer)
Mon Nov 28 17:52:45 2005
From: Florian Weimer <fw@deneb.enyo.de>
To: picardos@terra.es
Cc: bugtraq@securityfocus.com
Date: Mon, 28 Nov 2005 22:55:25 +0100
In-Reply-To: <20051128163954.6624.qmail@securityfocus.com>
(picardos@terra.es's message of "28 Nov 2005 16:39:54 -0000")
Message-ID: <87br04xws2.fsf@mid.deneb.enyo.de>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
> It has been identified a vulnerability in the Cisco IOS Web
> Server. An attacker can inject arbitrary code in some of the
> dynamically generated web pages. To succesfully exploit the
> vulnerability the attacker only needs to know the IP of the
> Cisco. THERE'S NO NEED TO HAVE ACCESS TO THE WEB SERVER! Once the
> code has been inyected, attacker must wait until the admin browses
> some of the affected web pages.
Isn't your exploit somewhat complicated? Just put
<img src="http://192.0.2.1/level/15/configure/-/enable/secret/mypassword"/>
on a web page, and trick the victim to visit it while he or she is
logged into the Cisco router at 192.0.2.1 over HTTP. This has been
dubbed "Cross-Site Request Forgery" a couple of years ago, but the
authors of RFC 2109 were already aware of it in 1997. At that time,
browser-side countermeasures were proposed (such as users examining
the HTML source code *cough*), but current practice basically mandates
that browsers transmit authentication information when following
cross-site links.
Such attacks are probably more problematic on low-end NAT routers
whose internal address defaults to 192.168.1.1 and which generally
offer HTTP access, which makes shotgun exploitation easier. So much
for the "put your Windows box behind a NAT router" advice you often
read.
