CVE-2026-4003 | felixmartinez Users manager Plugin up to 1.1.15 on WordPress AJAX Endpoint userspn_ajax_nopriv_server userspn_secret_token authorization

VDB-356010 · CVE-2026-4003 · GCVE-0-2026-4003 FELIXMARTINEZ USERS MANAGER PLUGIN UP TO 1.1.15 ON WORDPRESS AJAX ENDPOINT USERSPN_AJAX_NOPRIV_SERVER USERSPN_SECRET_TOKEN AUTHORIZATION HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 8.4 $0-$5k 0.58+ Summaryinfo A vulnerability was found in felixmartinez Users manager Plugin up to 1.1.15 on WordPress and classified as critical. The affected element is the function userspn_ajax_nopriv_server of the component AJAX Endpoint. The manipulation of the argument userspn_secret_token results in authorization. This vulnerability is known as CVE-2026-4003. It is possible to launch the attack remotely. No exploit is available. It is suggested to upgrade the affected component. Detailsinfo A vulnerability was found in felixmartinez Users manager Plugin up to 1.1.15 on WordPress. It has been classified as critical. Affected is the function userspn_ajax_nopriv_server of the component AJAX Endpoint. The manipulation of the argument userspn_secret_token with an unknown input leads to a authorization vulnerability. CWE is classifying the issue as CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes: The 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. The weakness was published by Ha Gia Bao. The advisory is available at wordfence.com. This vulnerability is traded as CVE-2026-4003 since 03/11/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are known, but there is no available exploit. Upgrading to version 1.0.31 eliminates this vulnerability. Productinfo Type WordPress Plugin Vendor felixmartinez Name Users manager Plugin Version 1.1.0 1.1.1 1.1.2 1.1.3 1.1.4 1.1.5 1.1.6 1.1.7 1.1.8 1.1.9 1.1.10 1.1.11 1.1.12 1.1.13 1.1.14 1.1.15 CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 8.5 VulDB Meta Temp Score: 8.4 VulDB Base Score: 7.3 VulDB Temp Score: 7.0 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 9.8 CNA Vector (Wordfence): 🔒 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Authorization CWE: CWE-862 / CWE-863 / CWE-285 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: Users manager Plugin 1.0.31 Timelineinfo 03/11/2026 CVE reserved 04/08/2026 +27 days Advisory disclosed 04/08/2026 +0 days VulDB entry created 04/08/2026 +0 days VulDB entry last update Sourcesinfo Advisory: wordfence.com Researcher: Ha Gia Bao Status: Confirmed CVE: CVE-2026-4003 (🔒) GCVE (CVE): GCVE-0-2026-4003 GCVE (VulDB): GCVE-100-356010 Entryinfo Created: 04/08/2026 08:01 Changes: 04/08/2026 08:01 (68) Complete: 🔍 Cache ID: 99:972:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸