No offence meant, but in all of your advisory only the control-code stuff and
possibly pissing off IPS/IDS systems makes sense.
But you need to have the user click a URL on a page you control. If a URL he
clicks on your site makes the IPS/IDS shout alerts, he might just get a clue,
and suspect your site instead of the site you linked to. Either way, it's
harmless, as long as there are no weird bugs in browsers concerning this. But
even then it's just as easy to make your own webserver spew out the harmful
data.
Now correct me if I'm wrong, but your cache poisoning in combination with
redirection only works if you can edit the html files accessed. Well now, if
you can edit the html files, you can just put redirects in there. Now, I agree
that it's a bug, but it's not a _security_ bug.
Other than that, the fact that the Host header is used to make redirects, is
absolutely normal, not a bug, not a security bug by a long shot. If the user
can reach a server with a certain hostname, getting a redirect with the same
hostname is something you'd want. The fact that you can manually craft a header
with a fake hostname doesn't mean you can get a user's browser to do that.
You have a nice "Proof of Concept" on your site, where you put some JavaScript
in the Host header of the request. But how would you ever get a user's browser
to have that crafted header? If you can control the browser to that extent,
there are much much worse things you can do. And if you craft a URL with that
as a hostname, the browser will not be able to resolve it to an IP.
Greetings,
Rogier
-----Original Message-----
From: hugo@infohacking.com [mailto:hugo@infohacking.com]
Sent: woensdag 14 februari 2007 6:21
To: bugtraq@securityfocus.com
Subject: Apache Multiple Injection Vulnerabilities
There's a new advisory at:
http://www.infohacking.com/INFOHACKING_RESEARCH/Our_Advisories/apache/inde
x.html
Summarizing:
"1.- HTTP 404 error response almost arbitrary injection (Apache)
Impact right now:
a) fake virus injection in Apache 404 HTTP responses wich can lead in
alarms on corporate gateway antivirus, lose of trust on supposed trusted
sites, end user paranoid...
b) Control codes injection -backspaces, etc.- thus allowing script
injection in the server response. Right now it seems that this
vulnerability is not
affecting real browsers, just because of the "backspace" escaping in the
clients, or due to other things. Anyway, the problem is that echoing back
control codes is a violation of the Content-Type charset in the response
and is IMHO a security risk.
Impact in the future: REAL injection in Apache 404 HTTP responses of
almost any kind of file, that is virus, binaries, trojans, etc. The
attacker must
be able to modify the "Content-Type" HTTP header of the server response.
Also, due to some restrictions in the injected "payload", the attacker
must avoid
using some chars like null bytes.
2.- Location HTTP header injection in server redirect responses (Apache,
IIS, Zeus 3.2, Google Web Server, Jigsaw/2.2.5, probably many
others)
Impact: Depending on the affected web server it could be a Denial of
Service -when combined with a proxy caché poisoning-, HTTP URL
redirection, etc."
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