The Nexter Extension – Security, Performance, Code Snippets & Site Toolkit plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 4.7.11 The vulnerability exists because the /?reset-view handler in roleswitchertoviewadminas() performs no nonce or capability check when the supplied username matches the authenticated caller, and because the plugin's only cleanup mechanism — the profileupdate hook — does not fire when WordPress performs a bulk role change via wp-admin/users.php?action=promote, which calls WPUser::setrole() directly and leaves a stale administrator value in the nxtextviewadminoriginalrole user meta. This makes it possible for authenticated attackers with Subscriber-level access or above to restore the stale stored Administrator role to their own account, effectively escalating their privileges to Administrator. Exploitation requires that the attacker's account previously held the Administrator role and used the View Admin Role Switcher feature before being demoted specifically through the bulk role-change control rather than the Edit User screen, as only the bulk path bypasses the profileupdate hook that would otherwise have cleared the stored original role.

The Nexter Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via multiple widgets in all versions up to, and including, 4.5.4 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

The Nexter Extension – Site Enhancements Toolkit plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'nxt-year' shortcode in all versions up to, and including, 4.4.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.