Thunderbird, Firefox ESR and Firefox are vulnerable to sandbox restrictions bypass. A remote unauthenticated user could cause memory corruption in the parent process due to the lack of parameter validation on IPC messages resulting in a system hang.
www.securityfocus.com/bid/103388
www.securitytracker.com/id/1040514
access.redhat.com/errata/RHSA-2018:0526
access.redhat.com/errata/RHSA-2018:0527
access.redhat.com/errata/RHSA-2018:0647
access.redhat.com/errata/RHSA-2018:0648
access.redhat.com/security/updates/classification/#critical
bugzilla.mozilla.org/show_bug.cgi?id=1428947
lists.debian.org/debian-lts-announce/2018/03/msg00010.html
lists.debian.org/debian-lts-announce/2018/03/msg00029.html
security.gentoo.org/glsa/201810-01
security.gentoo.org/glsa/201811-13
usn.ubuntu.com/3545-1/
usn.ubuntu.com/3596-1/
www.debian.org/security/2018/dsa-4139
www.debian.org/security/2018/dsa-4155
www.mozilla.org/en-US/security/advisories/mfsa2018-07/
www.mozilla.org/security/advisories/mfsa2018-06/
www.mozilla.org/security/advisories/mfsa2018-07/
www.mozilla.org/security/advisories/mfsa2018-09/