For RHEL 7, add EPEL repo:

yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
subscription-manager repos --enable "rhel-*-optional-rpms" --enable "rhel-*-extras-rpms"  --enable "rhel-ha-for-rhel-*-server-rpms"

And install exfat packages:

yum install -y exfat-utils fuse fuse-exfat

For RHEL 8 EPEL repo is not completed yet. Repo can be added:

yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm

But it will lack exfat packages, will need to compile from source (easy):

sudo -i
yum group install 'Development Tools'
yum install fuse-devel gcc autoconf automake git
cd /usr/local/src && git clone https://github.com/relan/exfat.git
cd exfat
autoreconf --install
./configure --prefix=/usr
make && make install
make clean

From: https://access.redhat.com/solutions/70050