Mozilla Firefox is vulnerable to use-after-free vulnerability. This occurs during a font face manipulation when a font face is freed while still in use. An attacker could cause a denial of service conditions resulting an application crash.
www.securityfocus.com/bid/102783
www.securitytracker.com/id/1040270
access.redhat.com/errata/RHSA-2018:0122
access.redhat.com/errata/RHSA-2018:0262
access.redhat.com/security/updates/classification/#critical
bugzilla.mozilla.org/show_bug.cgi?id=1425000
lists.debian.org/debian-lts-announce/2018/01/msg00030.html
lists.debian.org/debian-lts-announce/2018/01/msg00036.html
usn.ubuntu.com/3544-1/
www.debian.org/security/2018/dsa-4096
www.debian.org/security/2018/dsa-4102
www.mozilla.org/en-US/security/advisories/mfsa2018-01/
www.mozilla.org/en-US/security/advisories/mfsa2018-03/
www.mozilla.org/security/advisories/mfsa2018-02/
www.mozilla.org/security/advisories/mfsa2018-03/
www.mozilla.org/security/advisories/mfsa2018-04/