CVE-2025-22496: Notif Bell WordPress Plugin XSS Vulnerability

CVE-2025-22496 Overview

CVE-2025-22496 is a stored Cross-Site Scripting (XSS) vulnerability in the MarMar8x Notif Bell WordPress plugin. The flaw affects all versions of Notif Bell up to and including 0.9.8. It stems from improper neutralization of user-supplied input during web page generation [CWE-79]. Authenticated attackers with high privileges can inject malicious scripts that persist in the application and execute in the browsers of other users who view the affected content. Because the scope changes (CVSS S:C), injected payloads can affect resources beyond the vulnerable component.

Critical Impact

Stored JavaScript payloads execute in victim browsers, enabling session token theft, administrative action forgery, and lateral movement into WordPress administrative surfaces.

Affected Products

• MarMar8x Notif Bell WordPress plugin versions up to and including 0.9.8
• WordPress sites with the Notif Bell plugin installed and activated
• Any downstream content or dashboards rendering plugin-controlled fields

Discovery Timeline

• 2025-03-27 - CVE-2025-22496 published to the National Vulnerability Database (NVD)
• 2026-06-17 - Last updated in the NVD database

Technical Details for CVE-2025-22496

Vulnerability Analysis

The Notif Bell plugin fails to properly sanitize and escape user-controlled input before rendering it within web pages. An attacker with high privileges submits crafted input containing HTML or JavaScript. The plugin stores that payload and later returns it to other users without encoding, causing script execution in their browsers.

Stored XSS is more impactful than reflected XSS because the payload persists server-side. Every user who loads the affected page becomes a target without any additional social engineering. Exploitation requires user interaction (UI:R), typically a victim visiting the page containing the injected content.

Root Cause

The root cause is missing output encoding and insufficient input validation in the plugin's rendering logic. WordPress provides sanitization helpers such as esc_html(), esc_attr(), and wp_kses(), but the plugin fails to apply them consistently on user-controlled fields. The vulnerability aligns with CWE-79: Improper Neutralization of Input During Web Page Generation.

Attack Vector

An attacker with high privileges submits a payload containing JavaScript into a Notif Bell input field. The plugin stores the payload without sanitization. When another user, typically an administrator or subscriber, loads the page that renders the stored data, the browser executes the injected script under the site's origin. Attackers can hijack sessions, forge privileged actions, or pivot to other WordPress plugins. Full technical details are available in the Patchstack advisory for the Notif Bell plugin.

Detection Methods for CVE-2025-22496

Indicators of Compromise

• Unexpected <script>, <iframe>, or onerror= attributes stored in Notif Bell database tables or post metadata
• Outbound requests from admin browser sessions to unfamiliar domains after loading pages that render notification content
• New or modified WordPress administrator accounts created shortly after admin page views
• Anomalous session cookie access patterns targeting wp-admin endpoints

Detection Strategies

• Inspect the wp_options, wp_postmeta, and plugin-specific tables for HTML tags or JavaScript event handlers in fields intended for plain text
• Deploy web application firewall (WAF) rules to alert on XSS-shaped payloads submitted to plugin endpoints
• Correlate authenticated POST requests to Notif Bell handlers with subsequent script execution events in browser telemetry

Monitoring Recommendations

• Enable WordPress audit logging for plugin configuration changes and content submissions by high-privilege accounts
• Monitor Content Security Policy (CSP) violation reports for inline script executions on WordPress admin pages
• Track privileged account activity, particularly modifications to plugin settings and notification templates

How to Mitigate CVE-2025-22496

Immediate Actions Required

• Deactivate the Notif Bell plugin on all WordPress installations running version 0.9.8 or earlier until a patched release is confirmed
• Audit stored plugin data for existing script payloads and remove any malicious content
• Rotate credentials and session tokens for administrator accounts that may have viewed injected content
• Restrict high-privilege account access using strong authentication and least-privilege principles

Patch Information

At the time of NVD publication, no vendor patch is referenced. Consult the Patchstack advisory for the latest remediation status and monitor the plugin's WordPress repository page for updates beyond version 0.9.8.

Workarounds

• Remove or disable the Notif Bell plugin until a fixed version is available
• Deploy a WAF with rules that block XSS payloads targeting the plugin's request handlers
• Enforce a strict Content Security Policy that disallows inline scripts on WordPress admin pages
• Limit the number of accounts holding high-privilege WordPress roles to reduce the pool of potential attackers

# Content Security Policy header example for WordPress
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'; frame-ancestors 'self'; report-uri /csp-report"