Point taken. But that'd be a non-issue on the browser's end as much as
site's that is allowing the rogue scripts (or malformed ads, as per your
example).
The fork of this mail thread clearly explains what I'm talking about. The
issue noted there is a simple DoS attack which every programming language
and platform is vulnerable too. Its called the "infinite loop". It is not a
'security vulnerability' by itself and is completely agnostic of the uri
handler (try http or anything instead of nntp).
Here's the simplified JS version of it (lets call it the Universal DoS --
yes, it'd work for every browser on the planet that can execute JS) -
<script>
while(1)alert('hello world');
</script>
Done!
Workaround:
None very intuitive. Maybe allow the user to terminate the script at every
iteration? specific time period? etc...
--------------------------------------------------
From: "Vladimir '3APA3A' Dubrovin" <3APA3A@xxxxxxxxxxxxxxxx>
Sent: Friday, May 28, 2010 11:47 PM
To: "John Smith" <at-x@xxxxxxxx>
Cc: "MustLive" <mustlive@xxxxxxxxxxxxxxxxxx>; "Susan Bradley"
<sbradcpa@xxxxxxxxxxx>; <bugtraq@xxxxxxxxxxxxxxxxx>
Subject: Re[2]: DoS vulnerabilities in Firefox, Internet Explorer, Chrome,
Opera and other browsers
Dear John Smith,
Actually, browser DoS may be quite serious vulnerability, depending on
nature of DoS. Think about e.g. banner or content exchange network,
social networks, web boards, etc where browser vulnerability may be
used against site or page because it will harm any visitors of this
site or page.
In case of this very vulnerability, most serious impact may be from
e-mail vector.
--Friday, May 28, 2010, 7:07:50 PM, you wrote to
mustlive@xxxxxxxxxxxxxxxxxx:
JS> Just a few cents - DoS in webbrowsers doesn't fall under the category
of
JS> "vulnerabilities" rather more of "annoyances". Although I don't deny
the
JS> fact that certain DoS attacks *may lead* or *may serve as hints* to
other
JS> more serious exploits, but that's a different topic and with ASLR in
the
JS> scene, a very grey area of discussion.
--
Skype: Vladimir.Dubrovin
~/ZARAZA http://securityvulns.com/
Стреляя во второй раз, он искалечил постороннего. Посторонним был я.
(Твен)