Trash:Talk:Internet Browser

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I have created a simple page that when opened in the browser freezes the 3DS system. I assume that too much memory is allocated to the JavaScript engine. This freeze can only be fixed by turning the system off and on again, but the communication switch works during this freeze. This is the page: R4wrz0rz0r 14:57, 20 June 2011 (CEST) I cannot access your should make a public link from dropbox menu.

Sorry, I thought putting it in the Public folder would just make it work: R4wrz0rz0r 00:56, 21 June 2011 (CEST) Here's a shortened link: Kiddyshaq34

I think it is not so easy because this browser using Apple Webkit.

I don't think this is exploitable in any way. To me, seems more like NULL pointer dereferencing. Here's my full theory, may be wrong tho:

  • the Javascript engine doesn't allocate memory for strings that are too long, but still keeps track of their length. (try generating a 2^31 characters long string, alert()'ing it shows an empty alert, however its length returns the expected value)
  • such strings point to NULL instead of pointing to a memory buffer with characters. Their size is checked before trying to read them to display them in an alert.
  • now, if you generate a 2^32 string, the length of the string is 0x100000000 characters. This value gets cut off to zero because it doesn't fit in a 32bit integer. Therefore the length property of the string is zero.
  • when trying to alert() this string, the security check described above does infact "0 < maxlength", so the string is considered short enough to be displayed. However, since it was made from strings being already too large, its pointer is NULL.
  • the browser tries to read from NULL, causing an exception. Probably said exception would trigger special stuff on dev/debug units, but was set to just enter an endless loop on retail units.

Long story short, nothing gets overwritten. Just an attempt at using a NULL pointer. This is only a theory though, I may be wrong. --Luigi2us 01:40, 13 August 2011 (CEST)

It seems to be not exploitable, I have tried to write some NOPs into memory after the 'exploit' code and it doesn't seem to work.--Lazymarek9614 18:37, 11 September 2011 (CEST)

Well I have seen a Google Chrome exploit that uses a null pointer. It executes the nopsled and the shellcode so that it generates an exception. I think that if you try that exploit on Chrome on your computer, it still works(I tried it on version 15.0.865.1000 with sandbox disabled, and it generated an exception(a few times). So I think that's a sign that Google and the Chromium team still haven't fixed the exploit yet, but my antivirus detects it). But what I said might be wrong and misleading. And sometimes null pointer dereferencing can be exploitable if you try and think harder. --Kiddyshaq34 22:00, 03 September 2011 (GMT)

I am not sure if this is any help, but browsing to this page in the 3DS browser, causes the page to take an age to load... (around 5 mins), when the page does finally load you can see dots, scrolling down a few times till you see symbols instead of dots, then tapping the lower screen causes a load of pop unders. I had tried other Android based exploits, that were all thrown out (page to big errors), but this one seems different. viewing some pop unders (ones with target like icons) cause some to close and more to open...

The exploit used can be seen here... --Madshaun1984 23:27, 01 September 2011 (GMT) I've got a link if anyone wants to try it out: --Kiddyshaq34 23:19, 02 September 2011 (GMT)

Not to mention, the 3DS hardware is surely a lot different from Android/phones. Scriptkiddyish attempts like running Android exploits on a 3DS will not work. --Luigi2us 15:35, 2 September 2011 (CEST)

That Android shellcode is crap for the 3DS. Also the memory map should be different. BTW: How can we find out the memory map like ROM area, display memory, ... ? --Lazymarek9614 20:00, 2 September 2011 (CEST)

The webkit has a lot of android based code in it... therefore it is not unreasonable to think that maybe (just maybe) and android based exploit would have an effect on the 3DS. My assumptions werent just based on the browsers webkit either... what other platforms do you know that run on arm cpu's and use the .APP file extension? Then theres the whole QR code compatibility, that seems all to similar to pre-existing android software... Now dont get me wrong im not suggesting that the 3DS is running android, but it seems to be some sort of hybrid that has some compatibility with android, of course my assumptions and theory's could be well off... but i'll leave it to you to prove me wrong. --Madshaun1984 19:02, 02 September 2011 (GMT)

And again a boring way freeze the web browser: --Lazymarek9614 18:03, 13 September 2011 (CEST) Here's a shortened link: --Kiddyshaq34 20:15, 13 September 2011 (BST)