View at Official ubuntu advisory, NVD, CVE.org · CVE detail
Freshness: upstream tracker timestamp is available; use API updated time as primary recency signal.
CVE-2012-4184 medium priority: Ubuntu including 4 source packages (firefox, seamonkey, thunderbird, xulrunner-1.9.2), 36 status rows across 9 suites (hardy, lucid, natty, oneiric, precise, quantal, raring, saucy, upstream): released 17, DNE 9, ignored 9, needs-triage 1.
The Chrome Object Wrapper (COW) implementation in Mozilla Firefox before 16.0, Firefox ESR 10.x before 10.0.8, Thunderbird before 16.0, Thunderbird ESR 10.x before 10.0.8, and SeaMonkey before 2.13 does not prevent access to properties of a prototype for a standard class, which allows remote attackers to execute arbitrary JavaScript code with chrome privileges via a crafted web site.