Memory safety bugs present in Firefox 61 and Firefox ESR 60.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Firefox < 62, Firefox ESR < 60.2, and Thunderbird < 60.2.1.
http://www.securityfocus.com/bid/105280
http://www.securitytracker.com/id/1041610
https://access.redhat.com/errata/RHSA-2018:2692
https://access.redhat.com/errata/RHSA-2018:2693
https://access.redhat.com/errata/RHSA-2018:3403
https://access.redhat.com/errata/RHSA-2018:3458
https://lists.debian.org/debian-lts-announce/2018/11/msg00011.html
https://security.gentoo.org/glsa/201810-01
https://security.gentoo.org/glsa/201811-13
https://usn.ubuntu.com/3761-1/
https://usn.ubuntu.com/3793-1/
https://www.debian.org/security/2018/dsa-4287
https://www.debian.org/security/2018/dsa-4327
https://www.mozilla.org/security/advisories/mfsa2018-20/
Source: MITRE
Published: 2018-10-18
Updated: 2018-12-06
Type: CWE-119
Base Score: 7.5
Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P
Impact Score: 6.4
Exploitability Score: 10
Severity: HIGH
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 3.9
Severity: CRITICAL