Is Nexter Extension safe? Known vulnerabilities and latest version

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 `role_switcher_to_view_admin_as()` performs no nonce or capability check when the supplied username matches the authenticated caller, and because the plugin's only cleanup mechanism — the `profile_update` hook — does not fire when WordPress performs a bulk role change via `wp-admin/users.php?action=promote`, which calls `WP_User::set_role()` directly and leaves a stale `administrator` value in the `nxtext_view_admin_original_role` 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 `profile_update` hook that would otherwise have cleared the stored original role.

The Nexter Extension – Site Enhancements Toolkit plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 4.4.6 via deserialization of untrusted input in the 'nxt_unserialize_replace' function. This makes it possible for unauthenticated attackers to inject a PHP Object. No known POP chain is present in the vulnerable software, which means this vulnerability has no impact unless another plugin or theme containing a POP chain is installed on the site. If a POP chain is present via an additional plugin or theme installed on the target system, it may allow the attacker to perform actions like delete arbitrary files, retrieve sensitive data, or execute code depending on the POP chain present.

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.

Improper Control of Generation of Code ('Code Injection') vulnerability in POSIMYTH Nexter Extension.This issue affects Nexter Extension: from n/a through 2.0.3.

Unauth. Reflected Cross-Site Scripting (XSS) vulnerability in POSIMYTH Nexter Extension plugin <= 2.0.3 versions.