Reported vulnerability
Users manager – PN <= 1.1.15 - Unauthenticated Privilege Escalation via Account Takeover via 'userspn_form_save' AJAX Action
Published 7 Apr 2026
Updated 8 Apr 2026
CVE-2026-4003
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Does this affect my version?
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Wordfence advisory
critical · CVSS 9.8The Users manager – PN plugin for WordPress is vulnerable to Privilege Escalation via Arbitrary User Meta Update in all versions up to and including 1.1.15. This is due to a flawed authorization logic check in the userspn_ajax_nopriv_server() function within the 'userspn_form_save' case. The conditional only blocks unauthenticated users when the user_id is empty, but when a non-empty user_id is supplied, execution bypasses this check entirely and proceeds to update arbitrary user meta via update_user_meta() without any authentication or authorization verification. Additionally, the nonce required for this AJAX endpoint ('userspn-nonce') is exposed to all visitors via wp_localize_script on the public wp_enqueue_scripts hook, rendering the nonce check ineffective as a security control. This makes it possible for unauthenticated attackers to update arbitrary user metadata for any user account, including the userspn_secret_token field.
Severity vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Users manager – PN
- Software
- plugin · userspn
- Affected versions
- Start version unspecified, through 1.1.15
- Fix availability
- Fix available
- Fixed versions
- 1.1.20
Recommended action
Update to version 1.1.20, or a newer patched version
Further references (1)
Data sources and licences
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Read licence termsSource: Wordfence
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Get help with this issueQuestions about this vulnerability
Which versions of Users manager – PN are affected?
Wordfence lists these affected versions: Start version unspecified, through 1.1.15. Use the version checker above to compare your installed release with this report.
Is a fix available for Users manager – PN?
Wordfence reports a fix for this issue in Users manager – PN. It lists these fixed versions: 1.1.20. Back up your website and test the recommended update before applying it to your live site.
Where can I find my installed plugin version?
In WordPress, open Plugins > Installed Plugins and find the version shown beneath the plugin name.
Does an affected version mean my website has been hacked?
An affected version means the installed release matches a vulnerability described in this report. It does not show whether anyone has exploited it on your website. The checker compares version numbers with stored reports; it does not inspect your website.