Severity: Critical
CVSS Score: 9.3
The layout engine in Mozilla Firefox 2 and 3 before 3.0.7, Thunderbird before 2.0.0.21, and SeaMonkey 1.1.15 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via vectors related to nsCSSStyleSheet::GetOwnerNode, events, and garbage collection, which triggers memory corruption.