Updated firefox packages fix security vulnerabilities

Updated nss and firefox packages fix security vulnerabilities: Security researcher SkyLined reported a use-after-free issue in how audio is handled through the Web Audio API during MediaStream playback through interactions with the Web Audio API. This results in a potentially exploitable crash (CVE-2015-4477). Security researcher cgvwzq reported that it is possible to read cross-origin URLs following a redirect if performance.getEntries() is used along with an iframe to host a page. Navigating back in history through script, content is pulled from the browser cache for the redirected location instead of going to the original location. This is a same-origin policy violation and could allow for data theft (CVE-2015-7207). A heap-based buffer overflow flaw was found in the way NSS parsed certain ASN.1 structures. An attacker could use this flaw to create a specially crafted certificate which, when parsed by NSS, could cause it to crash, or execute arbitrary code, using the permissions of the user running an application compiled against the NSS library (CVE-2016-1950). Mozilla developer Tim Taubert used the Address Sanitizer tool and software fuzzing to discover a use-after-free vulnerability while processing DER encoded keys in the Network Security Services (NSS) libraries. The vulnerability overwrites the freed memory with zeroes (CVE-2016-1979). Several flaws were found in the processing of malformed web content. A web page containing malicious content could cause Firefox to crash or, potentially, execute arbitrary code with the privileges of the user running Firefox (CVE-2016-1952, CVE-2016-1954, CVE-2016-1957, CVE-2016-1958, CVE-2016-1960, CVE-2016-1961, CVE-2016-1962, CVE-2016-1974, CVE-2016-1964, CVE-2016-1965, CVE-2016-1966). Multiple security flaws were found in the graphite2 font library shipped with Firefox. A web page containing malicious content could cause Firefox to crash or, potentially, execute arbitrary code with the privileges of the user running Firefox (CVE-2016-1977, CVE-2016-2790, CVE-2016-2791, CVE-2016-2792, CVE-2016-2793, CVE-2016-2794, CVE-2016-2795, CVE-2016-2796, CVE-2016-2797, CVE-2016-2798, CVE-2016-2799, CVE-2016-2800, CVE-2016-2801, CVE-2016-2802).