Atomic Basic ModSecurity rule-set cannot be enabled: Invalid GPG Key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY.atomicorp.txt: No key found in given key data

Symptoms

Atomic Basic ModSecurity rule-set cannot be enabled at Tools & Settings > Web Application Firewall (ModSecurity) with the following error:

PLESK_ERROR: ModSecurity failed to install rule set. modsecurity_ctl failed: gpg:
<...>
NOKEY Invalid GPG Key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY.atomicorp.txt:
No key found in given key data
Command '/bin/bash < /tmp/tmpFHsuEp/aum' returned non-zero exit status 1
Unable to download tortix rule set

Cause

The GPG key mentioned in the error message is invalid or empty:

# cat /etc/pki/rpm-gpg/RPM-GPG-KEY.atomicorp.txt
#

Resolution

1. Connect to the Plesk server via SSH.

2. Download a valid GPG key from the official Atomicorp website:

   # wget -P /root https://www.atomicorp.com/RPM-GPG-KEY.atomicorp.txt

3. Remove the invalid GPG key:

   # rm -f /etc/pki/rpm-gpg/RPM-GPG-KEY.atomicorp.txt

4. Move the new GPG key to the corresponding directory:

   # mv /root/RPM-GPG-KEY.atomicorp.txt /etc/pki/rpm-gpg/RPM-GPG-KEY.atomicorp.txt

5. Restart Plesk services:

   # service sw-cp-server restart && service sw-engine restart

6. Enable Atomic Basic ModSecurity rule-set in Plesk.