Cross-site JavaScript injection using event handlers


shutdown reported a method of injecting running JavaScript code into a page
on another site using a modal alert to suspend an event handler while a new
page is being loaded. This vulnerability allows an attacker to steal any
confidential information the new page might contain, including any passwords
and cookies which might allow the attacker to log on to that site as the
victim.

shutdown also reported a variant using the two-argument form of eval() that
did  not  require  a  modal  dialog  and would be much less obtrusive.
moz_bug_r_a4 reported two variants that bypassed our initial fixes, one
using  "new  Script()",  the  other  extending the eval() attack using
window.__proto__

Note: Thunderbird shares the JavaScript engine with Firefox and could be
vulnerable if JavaScript were to be enabled in mail. This is not the default
setting and we strongly discourage users from running JavaScript in mail.

Workaround

Disable JavaScript until you can upgrade to a fixed version.

References

Original vulnerability:
[1]https://bugzilla.mozilla.org/show_bug.cgi?id=296514
Firefox 1.5 fix:
[2]https://bugzilla.mozilla.org/show_bug.cgi?id=296639
Alternate fix for Firefox 1.0.8/Mozilla Suite 1.7.13:
[3]https://bugzilla.mozilla.org/show_bug.cgi?id=316589
Variants:
[4]https://bugzilla.mozilla.org/show_bug.cgi?id=311024
[5]https://bugzilla.mozilla.org/show_bug.cgi?id=311619
[6]https://bugzilla.mozilla.org/show_bug.cgi?id=316589


This issue also affects RHEL3
This issue also affects RHEL2.1