ModSecurity is installed and enabled in Tools & Settings > Web Application Firewall (ModSecurity) > Web application firewall mode > On
A website hosted in Plesk fails to load, it is not possible to perform operations on the website such as manage WordPress, access webmail, access
robots.txtfile and the following error might be displayed in the browser:
PLESK_INFO: 403 Forbidden
PLESK_INFO: 500 Internal Server Error
PLESK_INFO: Service Unavailable. The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later.
A ModSecurity error message like below appears on the Logs page in Plesk at Domains > example.com > Logs:
ModSecurity: Access denied with code 403 (phase 2). Operator GE matched 5 at TX:anomaly_score. [file "/etc/apache2/modsecurity.d/rules/owasp_modsecurity_crs_3-plesk/REQUEST-949-BLOCKING-EVALUATION.conf"] [line "57"] [id "949110"] [msg "Inbound Anomaly Score Exceeded (Total Score: 5)"] [severity "CRITICAL"] [tag "application-multi"] [tag "language-multi"] [tag "platform-multi"] [tag "attack-generic"] [hostname "example.com"] [uri "/robots.txt"] [unique_id "XPsROH8AAQEAABEiZFcAAABC"]
ModSecurity Web Application Firewall is enabled with a very restrictive (strict) ruleset such as OWASP, Comodo, or a custom ruleset like Imunify360. Hence, some operations on the websites are blocked.
Consider one of the following options:
Switch to the Atomic ModSecurity ruleset: Log in to Plesk GUI > Tools & Settings > Web Application Firewall (ModSecurity) > Settings > Atomic Standard > Click OK to apply the changes