Re: Microsoft Windows image rendering DoS vuln
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I was using Firefox 1.0.2 when I first tried it, and I upgraded to
Firefox 1.0.3 the day I tried to recreate it myself. Maybe someone threw
a quick fix in before 1.0.3 was released? The vulnerability isn't
mentioned on the vulnerabilities page though.
It's interesting how the image was placed repeatedly on the page. Maybe
its not the large image that crashes it, but the attempt to process
multiple large images?
Randy wrote:
> I just tested it out on Windows XP sp2, firefox 1.0.3 and IE6
>
> No crash...
>
> -Randy
>
> On Thu, 21 Apr 2005, patrick wrote:
>
>> Ok everyone, someone sent me a copy of the site which was the link that
>> was originally sent with the vulnerability. Looking closer, it seems
>> that it may not be that the extremely large height and width properties
>> of the image in a site is what is causing the crash. However, I have not
>> had time to test it out, I will in a little bit, I need to finish a few
>> things.
>>
>> Here is the full page source (it's in the attachment). This is what I
>> was talking about though. Notice this in the page source:
>>
>> <code>
>> <!--
>> // Cache-busting LUBID bug.
>> var ran = Math.round(Math.random() * 899999) + 100000;
>> var lubid_string = "<img
>> src=\"http://hb.lycos.com/header?VID=6105&LHIG=1&ord="; + ran + "\"
>> height=\"1\" width=\"1\">";
>> document.write(lubid_string);
>> //-->
>> </script>
>> </code>
>>
>> The site also has this:
>>
>> <code>
>>
>> <img src="http://home.comcast.net/~squaresoft0/internet.jpg";
>> height="9999999" width=
>> "9999999"><br /><img
>> src="http://home.comcast.net/~squaresoft0/internet.jpg"; height="
>> 9999999" width="9999999">
>>
>> </code>
>>
>> Now, I will try setting up a site with just that code, and then a site
>> with both, and see what happens.
>>
>> I only briefly looked at the page source, so there may be more. Tell me
>> what you guys find.
>>
>> Jesse Morgan wrote:
>>
>>> Yes, it was SP2. My values were at 50000000 or something similar. I also
>>> created a 50000x50000 gif and tried that, still no luck.
>>> Unfortunately I didn't get my hands on the code.
>>> Also a friend's system rebooted after a bsod (he has an ATI video card
>>> and I have on-board video on a laptop)
>>>
>>> patrick wrote:
>>>
>>>> Hmm, don't think so, though, you said it crashed your computer...
>>>> was it
>>>> XP SP2? It sounds like it later in your email but I'm not sure... it's
>>>> quite interesting. Possibly his site had a different code than the one
>>>> you and I set up? He didn't go into much detail about the code except
>>>> that the "height" and "width" properties should be an enourmous amount.
>>>> Did you by any chance get the page source or no?
>>>
>>>
>>>> Jesse Morgan wrote:
>>>
>>>
>>>
>>>>> His site was up when I got the email and it did crash my computer.
>>>>> Livejorunal locked his account a few hours later.
>>>>> I too tried creating the exploit myself a few days later (windows xp
>>>>> sp2) and it failed to work. Maybe Microsoft somehow got a patch
>>>>> installed without us knowing?
>>>>>
>>>>> patrick wrote:
>>>>>
>>>>>
>>>>>> Andrew wrote:
>>>>>
>>>>>
>>>>>
>>>>>>> Alpha-Pi-Omicron Pi-Alpha-Nu-Tau-Omicron-C?
>>>>>>> Kappa-Alpha-Kappa-Omicron-Delta-Alpha-Iota-Mu-Omicron-Nu-Omicron-C?
>>>>>>> __ ___ __ _____ _ _
>>>>>>> ___ _ _
>>>>>>> / / /___\/ // _ / /\ /(_) __ _| |__ / __\___ _ _ _ __
>>>>>>> ___(_) |
>>>>>>> / / // // / \// / / /_/ / |/ _` | '_ \ / / / _ \| | | |
>>>>>>> '_ \ /
>>>>>>> __| | |
>>>>>>> / /___/ \_// /___/ //\ / __ /| | (_| | | | | / /__| (_) | |_| |
>>>>>>> | | |
>>>>>>> (__| | |
>>>>>>> \____/\___/\____/____/ \/ /_/ |_|\__, |_| |_| \____/\___/ \__,_|_|
>>>>>>> |_|\___|_|_|
>>>>>>>
>>>>>>> |___/
>>>>>>> Overview
>>>>>>>
>>>>>>> There exists a vulnerabilility in the way Microsoft Windows handles
>>>>>>> the rendering
>>>>>>> of images. By resizing an image with html properties to an extremely
>>>>>>> large size an
>>>>>>> attacker may perform a very quick and effective denial of service
>>>>>>> attack upon a
>>>>>>> victim.
>>>>>>>
>>>>>>>
>>>>>>> I. Description and PoC
>>>>>>>
>>>>>>> Only clients running Internet Explorer, Firefox, or Avant in Windows
>>>>>>> 2k or XP have
>>>>>>> been confirmed to be vulnerable. Opera does it's own image rendering
>>>>>>> and is not
>>>>>>> ulnerable to this method of attack. The status of Longhorn is not
>>>>>>> known. Other
>>>>>>> operating systems, including Mac OS X and Linux are not vulnerable.
>>>>>>>
>>>>>>> You may point your browser to this URL to see a live
>>>>>>> demonstration of
>>>>>>> this attack:
>>>>>>>
>>>>>>> http://www.livejournal.com/users/deeplolz
>>>>>>>
>>>>>>> This may cause an instant reboot or bluescreen detailing a problem
>>>>>>> with your video
>>>>>>> drivers. Other possibilities include an extended period of poor
>>>>>>> performance until
>>>>>>> next reboot, a short to medium period of nonfunctionality or a crash
>>>>>>> of the
>>>>>>> browser.
>>>>>>>
>>>>>>>
>>>>>>> II. Impact
>>>>>>>
>>>>>>> Because this attack can be performed anywhere an img src is allowed,
>>>>>>> there are
>>>>>>> many forums including blogs, messageboards, and others which are
>>>>>>> vulnerable. It
>>>>>>> is hopeful that Microsoft will release a patch for this attack as
>>>>>
>>>>>
>>>>> soon as
>>>>>
>>>>>>> possible.
>>>>>>>
>>>>>>>
>>>>>>> III. Solution
>>>>>>>
>>>>>>> Until a patch is released you are advised to use the Opera web
>>>>>>> browser. It might
>>>>>>> also be possible to write a script for the Firefox "GreaseMonkey"
>>>>>>> extension which
>>>>>>> performs a workaround for this attack. Such as setting height and
>>>>>>> width of images
>>>>>>> to 5000 pixels if they are currently set to render at over 5000.
>>>>>>>
>>>>>>>
>>>>>>> Very special shouts: Girlvinyl, Hepkitten, Confkids, and Frienditto
>>>>>>> (Come back!!!
>>>>>>> We need you badly, FD!)
>>>>>>>
>>>>>>> Shouts:
>>>>>>> LJD, LJ-Zeera, Encyclopedia Dramatica, Lulz News Network, Project
>>>>>>> Mayhem, Amalea,
>>>>>>> Wednesday Night Karate Explosion, The Gundanium Alloys Manufacturers
>>>>>>> Association,
>>>>>>> Richmond Flash Mob Society, RVA_BS, RVA_FYAD, Brad Fitzpatrick, Mena
>>>>>>> Trott, SALJ,
>>>>>>> The International Department of Internet Security, #telconinjas,
>>>>>>> undernet #drugs,
>>>>>>> The Kadaitcha Dancers, psychotic vegans, Warren Ellis, and pro-ana
>>>>>>> preteen girls.
>>>>>>>
>>>>>> Hmm, a few things.
>>>>>
>>>>>
>>>>>> 1) That site is down. Has been down ever since I got this email.
>>>>>> 2) I created a site with this HTML code:
>>>>>
>>>>>
>>>>>> /././././././././././././
>>>>>
>>>>>
>>>>>> <html>
>>>>>> <body>
>>>>>> <p>If you are using IE, YOU SUCK! Just kidding.<br>
>>>>>> If you're in Window$ though, this should crash your puter<br>
>>>>>> or give you a BSOD. HAVE FUN BUDDY! MUA HA HA!</p>
>>>>>
>>>>>
>>>>>> <img src="http://thepcelement.com/hardware/neowinscreenie.jpg";
>>>>>> height="9999999999999999999999999999999999999999999999999991"
>>>>>> width="999999999999999999999999999999999999999999999999999999999999999991">
>>>>>>
>>>>>
>>>>>
>>>>>> </body>
>>>>>> </html>
>>>>>
>>>>>
>>>>>> /./././././././././././
>>>>>
>>>>>
>>>>>> Yet no crash, this was on my Dad's PC running Window$ XP, no SP2,
>>>>>> Firefox and Internet Exploder, the image was all white, no
>>>>>> slowdown or
>>>>>> anything.
>>>>>
>>>>>
>>>>>> Can you tell me what I'm doing wrong and give me the source to that
>>>
>>> page
>>>
>>>>>> you had up as a live demonstration? I'm interested to see more about
>>>>>> this vulnerability.
>>>>>
>>>>>
>>>>>> Thanks for posting, have a nice day,
>>>
>>>
>>
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