full-disclosure - Re: Backdooring Image Files

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <5559abfc0612181841n16f74f21x839571517189a26b@mail.gmail.com>
Date: Tue, 19 Dec 2006 11:41:58 +0900
From: "HASEGAWA Yosuke " <yosuke.hasegawa@...il.com>
To: "pdp (architect)" <pdp.gnucitizen@...glemail.com>
Cc: full-disclosure@...ts.grok.org.uk, Web Security <websecurity@...appsec.org>
Subject: Re: Backdooring Image Files - security notice

Hi.

On 12/15/06, pdp (architect) <pdp.gnucitizen@...glemail.com> wrote:
> I will be brief. There is a rather lame/concerning technique, most of
> you know about, that allows JavaScript to be executed upon visiting an
> image file. This issue is not due to some browser error, although
> clearly IE has some issues with it, but it is due to web applications
> not sanitizing user supplied content in a form of links.

On Windows server, FindMimeFromData function can be used IE to
know what kind of file type it is determine with on the server side.
http://msdn.microsoft.com/workshop/networking/moniker/reference/functions/findmimefromdata.asp

Of course, a result may become  mismatch by the browser and
server side.

Or, adding "Content-Disposition: attachment" for response header,
It can be used to prevent executing script on browser directly.

-- 
HASEGAWA Yosuke
    yosuke.hasegawa@...il.com

_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/