CVE-2025-7963: WordPress Easy Waveform Player XSS Flaw

CVE-2025-7963 Overview

CVE-2025-7963 is a Stored Cross-Site Scripting [CWE-79] vulnerability in the Easy Waveform Player plugin for WordPress. The flaw affects all versions up to and including 1.2.2. It resides in the shortcode_easywaveformplayer() function, which fails to sanitize inputs and escape outputs. Authenticated users with Contributor-level access or higher can inject arbitrary JavaScript into pages. The injected scripts execute in the browser of any visitor who accesses the affected page.

Critical Impact
Authenticated contributors can persist malicious JavaScript in WordPress pages, enabling session theft, credential harvesting, and administrative account takeover when higher-privileged users view the injected content.

Affected Products

WordPress Easy Waveform Player plugin versions 1.0 through 1.2.2
WordPress sites permitting Contributor-level (or higher) accounts to use the shortcode
Any WordPress instance embedding the vulnerable shortcode_easywaveformplayer() shortcode

Discovery Timeline

2026-09-02 - CVE-2025-7963 published to NVD
2026-09-02 - Last updated in NVD database

Technical Details for CVE-2025-7963

Vulnerability Analysis

The vulnerability exists in the shortcode_easywaveformplayer() function within class-easywaveformplayer.php. The function processes shortcode attributes supplied by post authors and renders them into HTML output. Because the plugin does not sanitize the attribute values on input and does not escape them on output, attacker-supplied content is rendered verbatim into the DOM. WordPress Contributors can save posts containing shortcodes, so any user with this role or higher can persist a malicious payload. When an administrator, editor, or site visitor loads the page, the browser executes the injected script in the site's origin.

Stored XSS in WordPress plugins is frequently used to escalate from a low-privileged content role to full site compromise. Payloads typically create new administrator accounts, exfiltrate authentication cookies, or backdoor the theme via the plugin editor.

Root Cause

The root cause is insufficient input sanitization and missing output escaping in shortcode_easywaveformplayer(). Shortcode attribute values that should be treated as untrusted are passed directly into HTML context without functions such as esc_attr(), esc_html(), or wp_kses(). See the WordPress Plugin Source Code and the WordPress Plugin Changeset Details for the fix.

Attack Vector

Exploitation requires an authenticated session with Contributor role or above. The attacker submits a post or page containing the plugin shortcode with a crafted attribute value carrying JavaScript. Upon publication or preview by another user, the script executes with the viewer's privileges. Because the scope is changed (S:C), the payload can affect components beyond the vulnerable plugin, including the WordPress admin interface.

No verified public exploit code is available. Refer to the Wordfence Vulnerability Report for advisory details.

Detection Methods for CVE-2025-7963

Indicators of Compromise

Post or page content containing easywaveformplayer shortcode with attribute values embedding <script>, onerror=, onload=, or javascript: sequences
Newly created WordPress administrator accounts following Contributor post submissions
Unexpected outbound requests from browsers rendering plugin-hosted pages to attacker-controlled domains
Modifications to wp_options, theme files, or plugin files immediately after an admin previews a Contributor's post

Detection Strategies

Query the wp_posts table for shortcode instances containing suspicious attribute payloads such as HTML tags or event handlers
Deploy Web Application Firewall rules that inspect shortcode attributes for script content before content is stored
Enable WordPress audit logging to correlate Contributor post edits with subsequent privilege changes

Monitoring Recommendations

Monitor Content Security Policy (CSP) violation reports for inline script executions on plugin-rendered pages
Alert on creation or role change of WordPress users originating from admin browser sessions that recently loaded Contributor content
Track plugin version inventory to identify sites still running Easy Waveform Player <= 1.2.2

How to Mitigate CVE-2025-7963

Immediate Actions Required

Update the Easy Waveform Player plugin to the version published in the fix changeset referenced by the vendor
Audit existing posts and pages for easywaveformplayer shortcodes containing untrusted markup and remove malicious entries
Review Contributor and Author accounts for legitimacy and revoke unnecessary privileges
Rotate credentials and session tokens for administrator accounts that may have viewed injected content

Patch Information

The vendor addressed the vulnerability in the changeset documented in the WordPress Plugin Changeset Details. The fix introduces proper sanitization and escaping in shortcode_easywaveformplayer(). Consult the WordPress Plugin Developer Info page for the latest release.

Workarounds

Deactivate the Easy Waveform Player plugin until the patched version is installed
Restrict shortcode usage by removing the plugin's shortcode registration or limiting it to trusted roles via a custom current_user_can() capability check
Deploy a WAF rule blocking script tags and event handler attributes within shortcode payloads submitted to /wp-admin/post.php
Enforce a strict Content Security Policy that disallows inline JavaScript execution on pages rendering plugin output

bash

# Configuration example
wp plugin deactivate easy-waveform-player
wp plugin update easy-waveform-player
wp user list --role=contributor --fields=ID,user_login,user_email,user_registered