CVE-2026-3551 | rafasashi Custom New User Notification Plugin up to 1.2.0 on WordPress register_setting cross site scripting

VDB-357898 · CVE-2026-3551 · GCVE-0-2026-3551 RAFASASHI CUSTOM NEW USER NOTIFICATION PLUGIN UP TO 1.2.0 ON WORDPRESS REGISTER_SETTING CROSS SITE SCRIPTING HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 3.4 $0-$5k 1.05+ Summaryinfo A vulnerability, which was classified as problematic, was found in rafasashi Custom New User Notification Plugin up to 1.2.0 on WordPress. This affects the function register_setting. Executing a manipulation can lead to cross site scripting. This vulnerability appears as CVE-2026-3551. The attack may be performed from remote. There is no available exploit. Detailsinfo A vulnerability has been found in rafasashi Custom New User Notification Plugin up to 1.2.0 on WordPress and classified as problematic. This vulnerability affects the function register_setting. The manipulation with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. CVE summarizes: The Custom New User Notification plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's admin settings in all versions up to, and including, 1.2.0. This is due to insufficient input sanitization and output escaping on multiple settings fields including 'User Mail Subject', 'User From Name', 'User From Email', 'Admin Mail Subject', 'Admin From Name', and 'Admin From Email'. The settings are registered via register_setting() without sanitize callbacks, and the values retrieved via get_option() are echoed directly into HTML input value attributes without esc_attr(). This makes it possible for authenticated attackers, with Administrator-level access and above, to inject arbitrary web scripts in the plugin settings page that will execute whenever a user accesses that page. This could be used in multi-site installations where administrators of subsites could target super administrators. The weakness was presented by Muhammad Nur Ibnu Hubab. The advisory is available at wordfence.com. This vulnerability was named CVE-2026-3551 since 03/04/2026. The exploitation appears to be easy. The attack can be initiated remotely. Additional levels of successful authentication are necessary for exploitation. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1059.007 by the MITRE ATT&CK project. There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product. Productinfo Type WordPress Plugin Vendor rafasashi Name Custom New User Notification Plugin Version 1.0 1.1 1.2.0 CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 3.4 VulDB Meta Temp Score: 3.4 VulDB Base Score: 2.4 VulDB Temp Score: 2.4 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 4.4 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: Cross site scripting CWE: CWE-79 / CWE-94 / CWE-74 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: no mitigation known Status: 🔍 0-Day Time: 🔒 Timelineinfo 03/04/2026 CVE reserved 04/16/2026 +42 days Advisory disclosed 04/16/2026 +0 days VulDB entry created 04/16/2026 +0 days VulDB entry last update Sourcesinfo Advisory: wordfence.com Researcher: Muhammad Nur Ibnu Hubab Status: Not defined CVE: CVE-2026-3551 (🔒) GCVE (CVE): GCVE-0-2026-3551 GCVE (VulDB): GCVE-100-357898 Entryinfo Created: 04/16/2026 09:17 Changes: 04/16/2026 09:17 (65) Complete: 🔍 Cache ID: 99:6C1:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸