Firefox, up to and including the just-released Firefox 3, has a vulnerability.  Details about the exact nature of the bug are being withheld until a patch is made available.

Additional coverage of the issue can be found at:

http://dvlabs.tippingpoint.com/blog/2008/06/18/vulnerability-in-mozilla-firefox-30
http://news.yahoo.com/s/pcworld/20080619/tc_pcworld/147277
http://secunia.com/advisories/30761/
http://www.f-secure.com/weblog/archives/00001458.html
http://computerworld.com/action/article.do?command=viewArticleBasic&articleId=9100878&intsrc=hm_list
http://computerworld.com/action/article.do?command=viewArticleBasic&articleId=9100558&intsrc=hm_list

-- Bill Stearns, http://www.stearns.org