Comodo ModSecurity ruleset is not updated in Plesk: Failed to download the Comodo rule set

Symptoms

The following error is displayed on the Home page in Plesk:

PLESK_ERROR: Failed to update the ModSecurity rule set. Details

The following error is shown if clicking on the Details link:

PLESK_ERROR: Failed to update the ModSecurity rule set: modsecurity_ctl failed: Failed to download the Comodo rule set. The issue is on the waf.comodo.com side and we will alert them. You can also report the issue yourself on the Comodo forum - https://forums.comodo.com/free-modsecurity-rules-comodo-web-application-firewall-b223.0/ It might help fixing the issue earlier. For now, select the Atomic Standard rule set and try switching back to Comodo tomorrow.

Cause

The resource from which Comodo ruleset is updated - https://waf.comodo.com/ - is not accessible.

Resolution

The issue is on Comodo side and has already been reported to Comodo Support Team.

As a workaround temporarily switch to any other available ruleset:

1. Log into Plesk.
2. Go to Tools & Settings > Web Application Firewall (ModSecurity) > Settings tab.
3. Select any other ruleset except Comodo and apply changes.