CVE 2006-4565
Heap-based buffer overflow in Mozilla Firefox before 1.5.0.7, Thunderbird before 1.5.0.7, and SeaMonkey before 1.0.5 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a JavaScript regular expression with a "minimal quantifier."
See the 
CVE page on Mitre.org
for more details.
