CVE-2025-52750: Emu2 Plugin Reflected XSS Vulnerability

CVE-2025-52750 Overview

CVE-2025-52750 is a reflected Cross-Site Scripting (XSS) vulnerability in the Juergen Schulze Emu2 emu2-email-users-2 WordPress plugin. The flaw affects all versions of Emu2 up to and including 0.83b. Attackers can craft malicious URLs that, when clicked by an authenticated or unauthenticated victim, execute arbitrary JavaScript in the victim's browser session. The vulnerability is classified under [CWE-79] for improper neutralization of input during web page generation.

Critical Impact

Successful exploitation allows attackers to execute arbitrary script in the victim's browser, enabling session hijacking, credential theft, and redirection to attacker-controlled sites within the WordPress administrative context.

Affected Products

• Juergen Schulze Emu2 emu2-email-users-2 WordPress plugin
• All versions from initial release through 0.83b
• WordPress sites with the Emu2 plugin installed and active

Discovery Timeline

• 2025-10-22 - CVE-2025-52750 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2025-52750

Vulnerability Analysis

The Emu2 plugin fails to properly sanitize user-supplied input before reflecting it in HTML responses generated by the plugin. An attacker who crafts a URL containing JavaScript payloads can trigger script execution when a victim follows the link. The vulnerability requires user interaction, as indicated by the UI:R attribute in the CVSS vector, and operates across a security scope change (S:C), meaning script executes in a context beyond the vulnerable component itself.

Reflected XSS attacks against WordPress plugins typically target administrators or privileged users. Successful execution within a logged-in administrator session enables cookie theft, forced administrative actions, plugin modification, or pivot points for further compromise of the WordPress installation.

Root Cause

The root cause is improper neutralization of input during web page generation. The plugin echoes request parameters back into generated HTML without applying output encoding functions such as esc_html(), esc_attr(), or wp_kses(). WordPress provides these sanitization APIs specifically to prevent this class of injection, but the affected plugin code paths do not invoke them on relevant parameters.

Attack Vector

The attack vector is network-based and requires no authentication. An attacker hosts or distributes a crafted link pointing at the vulnerable WordPress site with a malicious payload embedded in a request parameter. When a victim clicks the link, the plugin reflects the payload into the response and the browser executes the injected script. Social engineering, phishing emails, or malicious advertisements are common delivery mechanisms.

No verified public proof-of-concept code is currently associated with this CVE. Refer to the Patchstack WordPress Vulnerability advisory for additional technical context.

Detection Methods for CVE-2025-52750

Indicators of Compromise

• HTTP request logs containing <script>, javascript:, onerror=, or onload= payloads in query strings targeting Emu2 plugin endpoints
• Outbound requests from administrator browsers to unfamiliar domains shortly after accessing WordPress admin pages
• Unexpected new administrator accounts or modified user roles in the WordPress database
• URL-encoded JavaScript payloads in web server access logs targeting /wp-content/plugins/emu2-email-users-2/ paths

Detection Strategies

• Inspect web server and WAF logs for reflected XSS signatures targeting plugin parameters
• Deploy Content Security Policy (CSP) reporting to capture inline script violations originating from plugin pages
• Monitor referrer headers on WordPress admin sessions for external origins that may indicate link-based delivery
• Correlate authentication events with anomalous admin actions following click-through traffic

Monitoring Recommendations

• Enable verbose access logging on /wp-admin/ and plugin directories with retention for at least 90 days
• Alert on requests containing common XSS keywords against any URL referencing the Emu2 plugin
• Track changes to WordPress user accounts, options, and installed plugins for unauthorized modifications
• Review browser developer tool consoles and server-side logs after any reported phishing attempt against site administrators

How to Mitigate CVE-2025-52750

Immediate Actions Required

• Deactivate and remove the Emu2 emu2-email-users-2 plugin if a patched release is not available
• Audit WordPress administrator accounts and force password resets for privileged users
• Invalidate active WordPress sessions to revoke any potentially stolen authentication cookies
• Enable a web application firewall rule set that filters reflected XSS payloads targeting plugin endpoints

Patch Information

No fixed version has been published for Emu2 as of the latest NVD update. All versions up to and including 0.83b remain affected. Site operators should monitor the Patchstack advisory for patch availability and apply updates immediately when released.

Workarounds

• Remove or disable the Emu2 plugin until an official fix is published
• Deploy a restrictive Content Security Policy that disallows inline script execution on WordPress admin pages
• Require administrators to access WordPress only through trusted bookmarks rather than email or chat links
• Restrict WordPress admin access by IP allowlisting at the web server or WAF layer

# Example: disable the vulnerable plugin via WP-CLI
wp plugin deactivate emu2-email-users-2
wp plugin delete emu2-email-users-2