Re: Apple Safari ... DoS Vulnerability

[Michal Zalewski <lcamtuf () coredump cx>]

> But what if www.evil.com has run an injection attack of some kind (SQL,
> XSS in blog comments, etc, etc) against www.stupid.com?
>
> Visitors to stupid.com then suffer a DoS...

In such a case, the attacker may just as well clobber body.innerHTML,
run a while (1) loop, or otherwise logically deny or alter service to
visitors without actually exploiting any specific bug - so I do not
see any significant benefit to killing this particular tab.

Crashing / hanging the entire browser is somewhat different, as it
bears some risk of data loss in plausible usage scenarios.
Unfortunately, most implementations do very little to prevent cases
that were permitted by standards in the first place (things such as
"while (1) str += str", "while (1) alert('foo')", looped blocking
XMLHttpRequest calls, ridiculously nested XML and other
expensive-to-render content, etc) - which makes finding new instances
somewhat futile and pointless, and a result, somewhat frowned upon on
security mailing lists (ugh).

/mz

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