Regex Tester & Validator
Test, validate and match regular expressions
Test, validate and match regular expressions
This regex matches Roundcube webmail IMAP login failure log entries, specifically catching failed plain text authentications. It extracts the client's IP address into a named capturing group called 'host' and checks for specific error messages in the Roundcube IMAP library. It is designed for fail2ban configurations to detect and block brute-force attacks on Debian-based systems.