This Metasploit module abuses an XSS vulnerability in versions prior to Firefox 39.0.3, Firefox ESR 38.1.1, and Firefox OS 2.2 that allows arbitrary files to be stolen. The vulnerability occurs in the PDF.js component, which uses Javascript to render a PDF inside a frame with privileges to read local files. The in-the-wild malicious payloads searched for sensitive files on Windows, Linux, and OSX. Android versions are reported to be unaffected, as they do not use the Mozilla PDF viewer.
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