A thunderbird security update has been released for CentOS 7.

CentOS Errata and Security Advisory 2020:0905 Important

Upstream details at : https://access.redhat.com/errata/RHSA-2020:0905

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

x86_64:
84bcf62441a4a7d12d7b6c3c1ab28505875145873108ccd5dbb8b5c244d16431 thunderbird-68.6.0-1.el7.centos.x86_64.rpm

Source:
697b4ca3940e84c7319aa3bf936d39e9f2077bbd97de652bd946301a75cf1efb thunderbird-68.6.0-1.el7.centos.src.rpm