Mozilla Firefox is vulnerable to use-after-free vulnerability. The vulnerability exists in the AppendAudioSegment() function in TrackEncoder.cpp that is triggered when the number of channels in an audio stream changes while the Opus encoder is in use. An unauthenticated, remote attacker can exploit this to disclose sensitive information.
www.securityfocus.com/bid/99057
www.securitytracker.com/id/1038689
access.redhat.com/errata/RHSA-2017:1440
access.redhat.com/errata/RHSA-2017:1561
access.redhat.com/security/updates/classification/#critical
bugzilla.mozilla.org/show_bug.cgi?id=1366595
www.debian.org/security/2017/dsa-3881
www.debian.org/security/2017/dsa-3918
www.mozilla.org/en-US/security/advisories/mfsa2017-16/
www.mozilla.org/security/advisories/mfsa2017-15/
www.mozilla.org/security/advisories/mfsa2017-16/
www.mozilla.org/security/advisories/mfsa2017-17/