CVE 2015-2731

Use-after-free vulnerability in the CSPService::ShouldLoad function in the microtask implementation in Mozilla Firefox before 39.0, Firefox ESR 38.x before 38.1, and Thunderbird before 38.1 allows remote attackers to execute arbitrary code by leveraging client-side JavaScript that triggers removal of a DOM object on the basis of a Content Policy.

See the CVE page on for more details.