How to protect against sudo vulnerability CVE-2021-3156
I strongly suggest installing the new sudo package as recommended in the bulletin that you linked to.
I believe https://access.redhat.com/errata/RHSA-2021:0221 is the relevant errata entry for RHEL 7, noting the release of sudo-1.8.23-10.el7_9.1.x86_64.rpm.