phpMyFAQ before 4.1.7, when configured to use PostgreSQL via the native pgsql PHP extension, declares an incorrect LIKE ESCAPE character ('=') in the Search/Database/Pgsql.php backend while escapeLikeWildcards() escapes user input with the '|' prefix. As a result, wildcard escaping is a no-op and user-supplied % and _ characters remain active LIKE wildcards. An unauthenticated attacker can submit such characters in the public FAQ search form to force maximally broad pattern matches and expensive sequential scans, resulting in a denial of service. The PDO PostgreSQL backend is not affected, and quotes remain escaped so this does not enable quote-breaking SQL injection or data exfiltration.

phpMyFAQ before 4.1.7, when configured to use PostgreSQL via the native pgsql PHP extension, declares an incorrect LIKE ESCAPE character ('=') in the Search/Database/Pgsql.php backend while escapeLikeWildcards() escapes user input with the '|' prefix. As a result, wildcard escaping is a no-op and user-supplied % and _ characters remain active LIKE wildcards. An unauthenticated attacker can submit such characters in the public FAQ search form to force maximally broad pattern matches and expensive sequential scans, resulting in a denial of service. The PDO PostgreSQL backend is not affected, and quotes remain escaped so this does not enable quote-breaking SQL injection or data exfiltration.