ご回答ありがとうございます。
トップページの記載見落としておりました。申し訳ございません。
8.6.6バージョンアップ後にmigrateしたほうが工数が掛からない方法になるのでしょうか。

[root@ip-x.x.x.x centos]# kusanagi status
Profile: kusanagi_html
FQDN: xxxxxx
Type: WordPress
KUSANAGI Version 8.4.6-2
aws

*** (active) Apache2 ***
● httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; vendor preset: disabled)
Active: active (running) since Fri 2022-11-11 20:08:45 JST; 2 weeks 2 days ago

*** (active) php7-fpm ***
● php7-fpm.service - The PHP FastCGI Process Manager
Loaded: loaded (/usr/lib/systemd/system/php7-fpm.service; enabled; vendor preset: disabled)
Active: active (running) since Fri 2022-11-11 20:08:45 JST; 2 weeks 2 days ago

*** (active) MariaDB ***
● mariadb.service - MariaDB 10.1.48 database server
Loaded: loaded (/usr/lib/systemd/system/mariadb.service; enabled; vendor preset: disabled)
Active: active (running) since Mon 2022-04-18 17:20:19 JST; 7 months 10 days ago

*** ruby ***
KUSANAGI Ruby is not installed yet

*** add-on ***

*** Cache Status ***
bcache on
fcache off

*** WAF ***
off

*** SELinux ***
off

Done.

[root@ip-x.x.x.x centos]# kusanagi --version
KUSANAGI Version 8.4.6-2
Done.

[root@ip-x.x.x.x centos]# yum check-update
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
epel/x86_64/metalink                                                                                                      | 5.8 kB  00:00:00     
 * base: download.cf.centos.org
 * epel: d2lzkl7pfhq30w.cloudfront.net
 * extras: download.cf.centos.org
 * updates: download.cf.centos.org
base                                                                                                                      | 3.6 kB  00:00:00     
epel                                                                                                                      | 4.7 kB  00:00:00     
extras                                                                                                                    | 2.9 kB  00:00:00     
groonga-centos                                                                                                            | 3.0 kB  00:00:00     
kusanagi                                                                                                                  | 2.9 kB  00:00:00     
http://yum.mariadb.org/10.1/centos7-amd64/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found
Trying other mirror.
To address this issue please refer to the below wiki article 

https://wiki.centos.org/yum-errors

If above article doesn't help to resolve this issue please use https://bugs.centos.org/.

updates                                                                                                                   | 2.9 kB  00:00:00     
zabbix                                                                                                                    | 2.9 kB  00:00:00     
zabbix-non-supported                                                                                                      | 2.9 kB  00:00:00     
(1/3): epel/x86_64/updateinfo                                                                                             | 1.0 MB  00:00:00     
(2/3): epel/x86_64/primary_db                                                                                             | 7.0 MB  00:00:00     
(3/3): kusanagi/primary_db                                                                                                | 680 kB  00:00:00     

ImageMagick.x86_64                                               6.9.10.68-6.el7_9                                                 updates       
bash.x86_64                                                      4.2.46-35.el7_9                                                   updates       
bind-export-libs.x86_64                                          32:9.11.4-26.P2.el7_9.10                                          updates       
bind-libs.x86_64                                                 32:9.11.4-26.P2.el7_9.10                                          updates       
bind-libs-lite.x86_64                                            32:9.11.4-26.P2.el7_9.10                                          updates       
bind-license.noarch                                              32:9.11.4-26.P2.el7_9.10                                          updates       
bind-utils.x86_64                                                32:9.11.4-26.P2.el7_9.10                                          updates       
binutils.x86_64                                                  2.27-44.base.el7_9.1                                              updates       
ca-certificates.noarch                                           2022.2.54-74.el7_9                                                updates       
certbot.noarch                                                   1.11.0-2.el7                                                      epel          
cloud-init.x86_64                                                19.4-7.el7.centos.6                                               updates       
cronie.x86_64                                                    1.4.11-24.el7_9                                                   updates       
cronie-anacron.x86_64                                            1.4.11-24.el7_9                                                   updates       
cyrus-sasl.x86_64                                                2.1.26-24.el7_9                                                   updates       
cyrus-sasl-devel.x86_64                                          2.1.26-24.el7_9                                                   updates       
cyrus-sasl-lib.x86_64                                            2.1.26-24.el7_9                                                   updates       
device-mapper.x86_64                                             7:1.02.170-6.el7_9.5                                              updates       
device-mapper-libs.x86_64                                        7:1.02.170-6.el7_9.5                                              updates       
dhclient.x86_64                                                  12:4.2.5-83.el7.centos.1                                          updates       
dhcp-common.x86_64                                               12:4.2.5-83.el7.centos.1                                          updates       
dhcp-libs.x86_64                                                 12:4.2.5-83.el7.centos.1                                          updates       
dmidecode.x86_64                                                 1:3.2-5.el7_9.1                                                   updates       
epel-release.noarch                                              7-14                                                              epel          
expat.x86_64                                                     2.1.0-15.el7_9                                                    updates       
expat-devel.x86_64                                               2.1.0-15.el7_9                                                    updates       
glib2.x86_64                                                     2.56.1-9.el7_9                                                    updates       
glibc.x86_64                                                     2.17-326.el7_9                                                    updates       
glibc-common.x86_64                                              2.17-326.el7_9                                                    updates       
glibc-devel.x86_64                                               2.17-326.el7_9                                                    updates       
glibc-headers.x86_64                                             2.17-326.el7_9                                                    updates       
groonga-release.noarch                                           2021.10.30-1                                                      groonga-centos
grub2.x86_64                                                     1:2.02-0.87.0.1.el7.centos.9                                      updates       
grub2-common.noarch                                              1:2.02-0.87.0.1.el7.centos.9                                      updates       
grub2-pc.x86_64                                                  1:2.02-0.87.0.1.el7.centos.9                                      updates       
grub2-pc-modules.noarch                                          1:2.02-0.87.0.1.el7.centos.9                                      updates       
grub2-tools.x86_64                                               1:2.02-0.87.0.1.el7.centos.9                                      updates       
grub2-tools-extra.x86_64                                         1:2.02-0.87.0.1.el7.centos.9                                      updates       
grub2-tools-minimal.x86_64                                       1:2.02-0.87.0.1.el7.centos.9                                      updates       
gssproxy.x86_64                                                  0.7.0-30.el7_9                                                    updates       
gzip.x86_64                                                      1.5-11.el7_9                                                      updates       
kbd.x86_64                                                       1.15.5-16.el7_9                                                   updates       
kbd-legacy.noarch                                                1.15.5-16.el7_9                                                   updates       
kbd-misc.noarch                                                  1.15.5-16.el7_9                                                   updates       
kernel.x86_64                                                    3.10.0-1160.80.1.el7                                              updates       
kernel-headers.x86_64                                            3.10.0-1160.80.1.el7                                              updates       
kernel-tools.x86_64                                              3.10.0-1160.80.1.el7                                              updates       
kernel-tools-libs.x86_64                                         3.10.0-1160.80.1.el7                                              updates       
kexec-tools.x86_64                                               2.0.15-51.el7_9.3                                                 updates       
kpartx.x86_64                                                    0.4.9-135.el7_9                                                   updates       
krb5-devel.x86_64                                                1.15.1-54.el7_9                                                   updates       
krb5-libs.x86_64                                                 1.15.1-54.el7_9                                                   updates       
kusanagi.noarch                                                  8.7.7-2                                                           kusanagi      
kusanagi-ImageMagick.x86_64                                      6.7.8.9-19.el7                                                    kusanagi      
kusanagi-httpd.noarch                                            2.4.54-1                                                          kusanagi      
kusanagi-mozjpeg.x86_64                                          4.1.1-1.el7                                                       kusanagi      
kusanagi-nghttp2.noarch                                          1.51.0-1                                                          kusanagi      
kusanagi-nginx.noarch                                            1.23.2-1                                                          kusanagi      
kusanagi-openssl.noarch                                          3.0.7-1                                                           kusanagi      
kusanagi-php7.noarch                                             7.4.33-1                                                          kusanagi      
kusanagi-wp-cli.noarch                                           2.7.1-1.el7                                                       kusanagi      
libX11.x86_64                                                    1.6.7-4.el7_9                                                     updates       
libX11-common.noarch                                             1.6.7-4.el7_9                                                     updates       
libidn2.x86_64                                                   2.3.4-1.el7                                                       epel          
libkadm5.x86_64                                                  1.15.1-54.el7_9                                                   updates       
libwebp.x86_64                                                   0.3.0-10.el7_9                                                    updates       
libwebp-tools.x86_64                                             0.3.0-10.el7_9                                                    updates       
libxml2.x86_64                                                   2.9.1-6.el7_9.6                                                   updates       
libxml2-devel.x86_64                                             2.9.1-6.el7_9.6                                                   updates       
libxml2-python.x86_64                                            2.9.1-6.el7_9.6                                                   updates       
luajit.x86_64                                                    2.0.5-1.20220913.46e62cd.el7                                      epel          
microcode_ctl.x86_64                                             2:2.1-73.15.el7_9                                                 updates       
mod_ssl.x86_64                                                   1:2.4.6-97.el7.centos.5                                           updates       
monit.x86_64                                                     5.30.0-1.el7                                                      epel          
nettle.x86_64                                                    2.7.1-9.el7_9                                                     updates       
nfs-utils.x86_64                                                 1:1.3.0-0.68.el7.2                                                updates       
nspr.x86_64                                                      4.34.0-3.1.el7_9                                                  updates       
nss.x86_64                                                       3.79.0-4.el7_9                                                    updates       
nss-softokn.x86_64                                               3.79.0-4.el7_9                                                    updates       
nss-softokn-freebl.x86_64                                        3.79.0-4.el7_9                                                    updates       
nss-sysinit.x86_64                                               3.79.0-4.el7_9                                                    updates       
nss-tools.x86_64                                                 3.79.0-4.el7_9                                                    updates       
nss-util.x86_64                                                  3.79.0-1.el7_9                                                    updates       
openldap.x86_64                                                  2.4.44-25.el7_9                                                   updates       
openldap-devel.x86_64                                            2.4.44-25.el7_9                                                   updates       
openssh.x86_64                                                   7.4p1-22.el7_9                                                    updates       
openssh-clients.x86_64                                           7.4p1-22.el7_9                                                    updates       
openssh-server.x86_64                                            7.4p1-22.el7_9                                                    updates       
openssl.x86_64                                                   1:1.0.2k-25.el7_9                                                 updates       
openssl-devel.x86_64                                             1:1.0.2k-25.el7_9                                                 updates       
openssl-libs.x86_64                                              1:1.0.2k-25.el7_9                                                 updates       
polkit.x86_64                                                    0.112-26.el7_9.1                                                  updates       
postgresql-libs.x86_64                                           9.2.24-8.el7_9                                                    updates       
python.x86_64                                                    2.7.5-92.el7_9                                                    updates       
python-libs.x86_64                                               2.7.5-92.el7_9                                                    updates       
python-perf.x86_64                                               3.10.0-1160.80.1.el7                                              updates       
python2-certbot.noarch                                           1.11.0-2.el7                                                      epel          
python2-distro.noarch                                            1.5.0-1.el7                                                       epel          
rpm.x86_64                                                       4.11.3-48.el7_9                                                   updates       
rpm-build-libs.x86_64                                            4.11.3-48.el7_9                                                   updates       
rpm-libs.x86_64                                                  4.11.3-48.el7_9                                                   updates       
rpm-python.x86_64                                                4.11.3-48.el7_9                                                   updates       
rsync.x86_64                                                     3.1.2-11.el7_9                                                    updates       
rsyslog.x86_64                                                   8.24.0-57.el7_9.3                                                 updates       
sudo.x86_64                                                      1.8.23-10.el7_9.2                                                 updates       
systemd.x86_64                                                   219-78.el7_9.7                                                    updates       
systemd-libs.x86_64                                              219-78.el7_9.7                                                    updates       
systemd-sysv.x86_64                                              219-78.el7_9.7                                                    updates       
tuned.noarch                                                     2.11.0-12.el7_9                                                   updates       
tzdata.noarch                                                    2022e-1.el7                                                       updates       
unzip.x86_64                                                     6.0-24.el7_9                                                      updates       
virt-what.x86_64                                                 1.18-4.el7_9.1                                                    updates       
vsftpd.x86_64                                                    3.0.2-29.el7_9                                                    updates       
wpa_supplicant.x86_64                                            1:2.6-12.el7_9.2                                                  updates       
xz.x86_64                                                        5.2.2-2.el7_9                                                     updates       
xz-devel.x86_64                                                  5.2.2-2.el7_9                                                     updates       
xz-libs.x86_64                                                   5.2.2-2.el7_9                                                     updates       
zabbix-agent.x86_64                                              3.0.32-1.el7                                                      zabbix        
zlib.x86_64                                                      1.2.7-20.el7_9                                                    updates       
zlib-devel.x86_64                                                1.2.7-20.el7_9                                                    updates