Code execution through javascript: URLs — Mozilla

Mozilla security researcher moz_bug_r_a4 reported a arbitrary code execution attack using a javascript: URL. The Gecko engine features a JavaScript sandbox utility that allows the browser or add-ons to safely execute script in the context of a web page. In certain cases, javascript: URLs are executed in such a sandbox with insufficient context that can allow those scripts to escape from the sandbox and run with elevated privilege. This can lead to arbitrary code execution.