Security researcher Hidetake Jo of Microsoft Vulnerability Research reported that the properties set on an object passed to showModalDialog were readable by the document contained in the dialog, even when the document was from a different domain. This is a violation of the same-origin policy and could result in a website running untrusted JavaScript if it assumed the dialogArguments could not be initialized by another site. An anonymous security researcher, via TippingPoint's Zero Day Initiative, also independently reported this issue to Mozilla.
http://www.mozilla.org/security/announce/2010/mfsa2010-04.html
This issue has been addressed in following products: Red Hat Enterprise Linux 4 Red Hat Enterprise Linux 5 Via RHSA-2010:0112 https://rhn.redhat.com/errata/RHSA-2010-0112.html
firefox-3.5.8-1.fc12,xulrunner-1.9.1.8-1.fc12 has been submitted as an update for Fedora 12. http://admin.fedoraproject.org/updates/firefox-3.5.8-1.fc12,xulrunner-1.9.1.8-1.fc12
gnome-python2-extras-2.25.3-16.fc12,perl-Gtk2-MozEmbed-0.08-6.fc12.11,blam-1.8.5-22.fc12,gnome-web-photo-0.9-5.fc12,mozvoikko-1.0-8.fc12,firefox-3.5.8-1.fc12,xulrunner-1.9.1.8-1.fc12 has been submitted as an update for Fedora 12. http://admin.fedoraproject.org/updates/gnome-python2-extras-2.25.3-16.fc12,perl-Gtk2-MozEmbed-0.08-6.fc12.11,blam-1.8.5-22.fc12,gnome-web-photo-0.9-5.fc12,mozvoikko-1.0-8.fc12,firefox-3.5.8-1.fc12,xulrunner-1.9.1.8-1.fc12
galeon-2.0.7-20.fc12,gnome-python2-extras-2.25.3-16.fc12,perl-Gtk2-MozEmbed-0.08-6.fc12.11,blam-1.8.5-22.fc12,gnome-web-photo-0.9-5.fc12,mozvoikko-1.0-8.fc12,firefox-3.5.8-1.fc12,xulrunner-1.9.1.8-1.fc12 has been submitted as an update for Fedora 12. http://admin.fedoraproject.org/updates/galeon-2.0.7-20.fc12,gnome-python2-extras-2.25.3-16.fc12,perl-Gtk2-MozEmbed-0.08-6.fc12.11,blam-1.8.5-22.fc12,gnome-web-photo-0.9-5.fc12,mozvoikko-1.0-8.fc12,firefox-3.5.8-1.fc12,xulrunner-1.9.1.8-1.fc12
chmsee-1.0.1-15.fc11,epiphany-2.26.3-8.fc11,blam-1.8.5-18.fc11,pcmanx-gtk2-0.3.9-2.20100210svn.fc11,galeon-2.0.7-20.fc11,hulahop-0.4.9-12.fc11,eclipse-3.4.2-20.fc11,evolution-rss-0.1.4-10.fc11,gnome-web-photo-0.7-10.fc11,gnome-python2-extras-2.25.3-11.fc11,monodevelop-2.0-9.fc11,Miro-2.5.4-2.fc11,kazehakase-0.5.8-5.fc11,mozvoikko-0.9.7-0.11.rc1.fc11,google-gadgets-0.11.1-5.fc11,perl-Gtk2-MozEmbed-0.08-6.fc11.9,ruby-gnome2-0.19.3-6.fc11,yelp-2.26.0-11.fc11,epiphany-extensions-2.26.1-10.fc11,firefox-3.5.8-1.fc11,xulrunner-1.9.1.8-1.fc11 has been submitted as an update for Fedora 11. http://admin.fedoraproject.org/updates/chmsee-1.0.1-15.fc11,epiphany-2.26.3-8.fc11,blam-1.8.5-18.fc11,pcmanx-gtk2-0.3.9-2.20100210svn.fc11,galeon-2.0.7-20.fc11,hulahop-0.4.9-12.fc11,eclipse-3.4.2-20.fc11,evolution-rss-0.1.4-10.fc11,gnome-web-photo-0.7-10.fc11,gnome-python2-extras-2.25.3-11.fc11,monodevelop-2.0-9.fc11,Miro-2.5.4-2.fc11,kazehakase-0.5.8-5.fc11,mozvoikko-0.9.7-0.11.rc1.fc11,google-gadgets-0.11.1-5.fc11,perl-Gtk2-MozEmbed-0.08-6.fc11.9,ruby-gnome2-0.19.3-6.fc11,yelp-2.26.0-11.fc11,epiphany-extensions-2.26.1-10.fc11,firefox-3.5.8-1.fc11,xulrunner-1.9.1.8-1.fc11
seamonkey-2.0.3-1.fc12 has been pushed to the Fedora 12 stable repository. If problems still persist, please make note of it in this bug report.
firefox-3.5.8-1.fc11, xulrunner-1.9.1.8-1.fc11, chmsee-1.0.1-15.fc11, epiphany-2.26.3-8.fc11, blam-1.8.5-18.fc11, pcmanx-gtk2-0.3.9-2.20100210svn.fc11, galeon-2.0.7-20.fc11, hulahop-0.4.9-12.fc11, eclipse-3.4.2-20.fc11, evolution-rss-0.1.4-10.fc11, gnome-web-photo-0.7-10.fc11, gnome-python2-extras-2.25.3-11.fc11, monodevelop-2.0-9.fc11, Miro-2.5.4-2.fc11, kazehakase-0.5.8-5.fc11, mozvoikko-0.9.7-0.11.rc1.fc11, google-gadgets-0.11.1-5.fc11, perl-Gtk2-MozEmbed-0.08-6.fc11.9, ruby-gnome2-0.19.3-6.fc11, yelp-2.26.0-11.fc11, epiphany-extensions-2.26.1-10.fc11 has been pushed to the Fedora 11 stable repository. If problems still persist, please make note of it in this bug report.
firefox-3.5.8-1.fc12, xulrunner-1.9.1.8-1.fc12, gnome-python2-extras-2.25.3-16.fc12, perl-Gtk2-MozEmbed-0.08-6.fc12.11, blam-1.8.5-22.fc12, gnome-web-photo-0.9-5.fc12, mozvoikko-1.0-8.fc12, galeon-2.0.7-20.fc12 has been pushed to the Fedora 12 stable repository. If problems still persist, please make note of it in this bug report.