A firefox Security Update has been released for CentOS 7.

CentOS Errata and Security Advisory 2020:0085 Critical

Upstream details at : https://access.redhat.com/errata/RHSA-2020:0085

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

x86_64:
fc806ebbeb3b502135e880fc87d32fe05c431e5dde8faa0d7bdcae60c177c131 firefox-68.4.1-1.el7.centos.i686.rpm
f6af9cc40e6957387f1c1dc3917b80ae5a2d6f10d0fff3786fbc3f5c59d535a1 firefox-68.4.1-1.el7.centos.x86_64.rpm

Source:
011b1af2042a53e1a91910dc58a030a13122a01de9bd51532b2da584a400fd5c firefox-68.4.1-1.el7.centos.src.rpm