Mozilla has published security advisories, highlighting vulnerabilities in Firefox, Firefox ESR and Thunderbird on 19th November, 2020. It is recommended that you take the necessary precautions by ensuring your products are always updated.
Firefox ESR 78.5
For more information on Mozilla updates you can follow this URL:
The Guyana National CIRT recommends that users and administrators review these updates and apply them where necessary.
Mozilla releases security updates (19th November, 2020). Retrieved form US-Cert
Mozilla releases security updates (17th November, 2020). Retrieved from MS-ISAC