The Mozilla Foundation released updates for Firefox 62 and Firefox ESR 60.2 to fix several vulnerabilities, including two rated critical.
In Firefox 62 the critical issues are CVE-2018-12388 and CVE-2018-12390, which is also in Firefox ESR 60.2, Mozilla reported. Both are memory safety bugs that showed some evidence of memory corruption that possibly with enough effort could be used to run arbitrary code.
There are also three moderate issues shared between both that were addressed, CVE-2018-12395, CVE-2018-12396, CVE-20186-and CVE-2018-12397 while CVE-2018-12398 just affected Firefox 62.
All the vulnerabilities are fixed by updating to Firefox 63 and ESR 60.3.