Describe CVE-2012-3957.
What is CVE-2012-3957?
Heap-based buffer overflow in the nsBlockFrame::MarkLineDirty function in Mozilla Firefox before 15.0, Firefox ESR 10.x before 10.0.7, Thunderbird before 15.0, Thunderbird ESR 10.x before 10.0.7, and SeaMonkey before 2.12 allows remote attackers to execute arbitrary code via unspecified vectors..