A thunderbird security update has been released for CentOS 7.

CentOS Errata and Security Advisory 2020:0120 Important

Upstream details at :   https://access.redhat.com/errata/RHSA-2020:0120

The following updated files have been uploaded and are currently
syncing to the mirrors: ( sha256sum Filename )

x86_64:
4c599a08f131ecb7522d4c14aea2b129926c9d393d62724cf19596affeb6797b thunderbird-68.4.1-2.el7.centos.x86_64.rpm

Source:
b402421cc2103807c9bc82d49f692fc4d6f54bae26a9b79a7c74c5c343bed32f thunderbird-68.4.1-2.el7.centos.src.rpm