CVE-2025-14797: WordPress Same Category Posts XSS Flaw

CVE-2025-14797 Overview

CVE-2025-14797 is a Stored Cross-Site Scripting (XSS) vulnerability in the Same Category Posts plugin for WordPress, affecting all versions up to and including 1.1.19. The flaw resides in the widget title placeholder functionality, where the plugin applies htmlspecialchars_decode() to taxonomy term names before output. This decoding reverses the HTML entity encoding that WordPress applies for safety, allowing script payloads stored in taxonomy term names to render as executable markup. Authenticated attackers with Author-level access or higher can inject arbitrary JavaScript that executes when users view affected pages [CWE-79].

Critical Impact
Authenticated attackers with Author privileges can inject persistent JavaScript that executes in the browser context of any visitor, enabling session hijacking, content defacement, and privilege escalation attacks against administrators.

Affected Products

Same Category Posts plugin for WordPress — all versions through 1.1.19
WordPress sites permitting Author-level user registration with this plugin active
Any site using widgets that render taxonomy term names through the affected functions

Discovery Timeline

2026-01-24 - CVE-2025-14797 published to NVD
2026-04-15 - Last updated in NVD database

Technical Details for CVE-2025-14797

Vulnerability Analysis

The vulnerability stems from improper output encoding in the Same Category Posts plugin's widget rendering logic. WordPress core encodes taxonomy term names using HTML entities to prevent script injection at the storage and retrieval layers. The plugin reverses this protection by calling htmlspecialchars_decode() on term names before echoing them into the widget title placeholder output, transforming benign encoded strings such as <script> back into executable <script> tags.

Because the decoded output is written directly into rendered HTML without re-sanitization, any payload stored in a taxonomy term name becomes a stored XSS vector. The affected output paths exist at lines 639, 665, and 707 of same-category-posts.php in version 1.1.19. The Author-level privilege requirement limits the attack surface, but Authors on multi-user WordPress sites typically can create or edit taxonomy terms associated with their posts.

Root Cause

The root cause is the misuse of htmlspecialchars_decode() on user-controllable data prior to output. WordPress intentionally encodes taxonomy term names with htmlspecialchars() during storage and retrieval to neutralize markup. By decoding these values before rendering, the plugin reintroduces raw HTML and script content into the DOM, directly violating output encoding best practices for [CWE-79].

Attack Vector

An attacker authenticated as an Author or higher creates or edits a category, tag, or custom taxonomy term and embeds JavaScript within the term name. When a visitor loads a page containing the Same Category Posts widget that references the malicious term, the plugin decodes the term name and inserts the script into the page. User interaction is required (visiting the page), and the injected script executes in the browser context of every visitor, including administrators. See the WordPress Plugin Code Snippet for the vulnerable rendering logic.

// Vulnerable pattern (described in prose - no synthetic PoC):
// The plugin retrieves a taxonomy term name and applies
// htmlspecialchars_decode() before output, reversing WordPress's
// safety encoding and rendering attacker-controlled markup.

Detection Methods for CVE-2025-14797

Indicators of Compromise

Taxonomy term names containing HTML tags, <script> blocks, event handlers such as onerror=, or javascript: URIs
Unexpected outbound requests from visitor browsers to attacker-controlled domains originating on pages rendering the Same Category Posts widget
New or modified terms created by Author-level accounts shortly before user reports of suspicious browser behavior

Detection Strategies

Audit the wp_terms database table for term name values containing characters such as <, >, or &# that suggest encoded or raw markup
Review WordPress audit logs for taxonomy term creation and edits performed by Author-level accounts
Scan rendered widget output in staging environments for unencoded HTML originating from term names

Monitoring Recommendations

Enable a Content Security Policy (CSP) with reporting to surface inline script execution attempts on pages using the plugin
Monitor web server logs for requests to admin or taxonomy endpoints by low-privilege accounts
Alert on creation or modification of WordPress users assigned the Author role and on unusual taxonomy term activity

How to Mitigate CVE-2025-14797

Immediate Actions Required

Update the Same Category Posts plugin to a version later than 1.1.19 once the vendor publishes a fix
Audit all existing taxonomy terms for embedded HTML or script content and sanitize or delete suspicious entries
Review Author-level and higher user accounts; remove or downgrade accounts that are not required

Patch Information

A remediation commit is referenced in the WordPress Change Set for the Same Category Posts plugin. Administrators should upgrade to the patched release identified in the Wordfence Vulnerability Report.

Workarounds

Deactivate the Same Category Posts plugin until a patched release is installed
Restrict taxonomy term editing to Editor and Administrator roles using a capability management plugin
Deploy a Web Application Firewall (WAF) rule to block requests containing script tags in taxonomy term parameters
Apply a strict Content Security Policy (CSP) that disallows inline scripts on the public site

bash

# Example: list potentially malicious taxonomy terms via WP-CLI
wp term list category --fields=term_id,name,slug --format=table | grep -E '<|>|script|onerror'
wp term list post_tag --fields=term_id,name,slug --format=table | grep -E '<|>|script|onerror'

# Temporarily deactivate the vulnerable plugin
wp plugin deactivate same-category-posts