The Quiz and Survey Master (QSM) – Easy Quiz and Survey Maker plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 11.1.4. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for authenticated attackers, with contributor-level access and above, to create, modify, and delete quiz output templates stored in the mlwquizoutputtemplates database table, including storing unsanitized HTML content such as arbitrary script tags.

The Quiz And Survey Master plugin for WordPress is vulnerable to Arbitrary Shortcode Execution in versions up to and including 11.1.0. This is due to insufficient input sanitization and the execution of doshortcode() on user-submitted quiz answer text. User-submitted answers pass through sanitizetextfield() and htmlspecialchars(), which only strip HTML tags but do not encode or remove shortcode brackets [ and ]. When quiz results are displayed, the plugin calls doshortcode() on the entire results page output (including user answers), causing any injected shortcodes to be executed. This makes it possible for unauthenticated attackers to inject arbitrary WordPress shortcodes such as [qsmresult id=X] to access other users' quiz submissions without authorization, as the qsmresult shortcode lacks any authorization checks.

The Quiz and Survey Master (QSM) plugin for WordPress is vulnerable to SQL Injection via the 'mergedquestion' parameter in all versions up to, and including, 10.3.5. This is due to insufficient sanitization of user-supplied input before being used in a SQL query. The sanitizetextfield() function applied to the mergedquestion parameter does not prevent SQL metacharacters like ), OR, AND, and # from being included in the value, which is then directly concatenated into a SQL IN() clause without using $wpdb->prepare() or casting values to integers. This makes it possible for authenticated attackers, with Contributor-level access and above, to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database.

The Quiz and Survey Master (QSM) WordPress plugin before 10.2.3 does not have CSRF check in place when updating its settings, which could allow attackers to make a logged in admin change them via a CSRF attack.

The Quiz and Survey Master (QSM) WordPress plugin before 9.2.1 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfilteredhtml capability is disallowed (for example in multisite setup).

The Quiz and Survey Master (QSM) WordPress plugin before 9.1.1 fails to validate and escape certain Quiz fields before displaying them on a page or post where the Quiz is embedded, which could allows contributor and above roles to perform Stored Cross-Site Scripting (XSS) attacks.

The Quiz and Survey Master (QSM) WordPress plugin before 9.1.0 does not properly sanitise and escape some of its Quizz settings, which could allow high privilege users such as contributor to perform Stored Cross-Site Scripting attacks

The Quiz and Survey Master (QSM) WordPress plugin before 9.0.2 does not validate and escape some of its Quiz fields before outputting them back in a page/post where the Quiz is embed, which could allow users with the contributor role and above to perform Stored Cross-Site Scripting attacks