CVE-2025-15377: Sosh Share Buttons WordPress CSRF Flaw

CVE-2025-15377 Overview

The Sosh Share Buttons plugin for WordPress contains a Cross-Site Request Forgery (CSRF) vulnerability in all versions up to and including 1.1.0. This security flaw stems from missing nonce validation on the admin_page_content function, allowing unauthenticated attackers to manipulate plugin settings through forged requests when they can successfully trick a site administrator into clicking a malicious link.

Critical Impact

Unauthenticated attackers can modify plugin settings without authorization by exploiting the missing CSRF protection, potentially leading to site defacement or malicious content injection through social sharing buttons.

Affected Products

• Sosh Share Buttons WordPress Plugin version 1.1.0 and earlier
• WordPress sites with vulnerable plugin versions installed
• Any WordPress installation running the affected plugin without additional CSRF protection

Discovery Timeline

• 2026-01-14 - CVE-2025-15377 published to NVD
• 2026-01-14 - Last updated in NVD database

Technical Details for CVE-2025-15377

Vulnerability Analysis

This Cross-Site Request Forgery vulnerability exists due to inadequate security controls in the plugin's administrative interface. The admin_page_content function, located in sosh.class.php, processes form submissions that modify plugin settings without properly validating the request's origin. WordPress provides built-in nonce verification functions (wp_nonce_field() and wp_verify_nonce()) specifically to prevent CSRF attacks, but this plugin fails to implement these critical security measures.

When an administrator visits the plugin settings page and submits configuration changes, the function processes these requests based solely on the HTTP parameters received without confirming the request originated from a legitimate admin session. This architectural oversight creates an opportunity for attackers to craft malicious pages that submit unauthorized configuration changes on behalf of authenticated administrators.

Root Cause

The root cause is the absence of WordPress nonce validation in the admin_page_content function within sosh.class.php at line 138. The function directly processes form data and updates plugin options without checking for a valid security token, violating WordPress security best practices for administrative form handling.

Attack Vector

An attacker exploits this vulnerability by creating a malicious webpage containing a hidden form or JavaScript that automatically submits a request to the WordPress admin panel with attacker-controlled settings. The attack requires social engineering to lure an authenticated administrator to visit the malicious page. Once the admin visits the attacker's page while logged into WordPress, the browser automatically includes session cookies with the forged request, causing WordPress to accept the malicious settings change as if it came from the legitimate administrator.

The vulnerability is exploited through the following attack flow:

1. Attacker crafts a malicious HTML page with a form targeting the plugin's settings endpoint
2. The form contains hidden fields with attacker-desired configuration values
3. The malicious page is sent to or visited by an authenticated WordPress administrator
4. Upon page load, JavaScript automatically submits the hidden form
5. The administrator's browser sends the request with valid session cookies
6. The plugin processes the request without nonce validation, applying malicious settings

For detailed technical analysis, refer to the WordPress Plugin Code Review and the Wordfence Vulnerability Report.

Detection Methods for CVE-2025-15377

Indicators of Compromise

• Unexpected changes to Sosh Share Buttons plugin configuration settings
• Modified social sharing URLs pointing to suspicious external domains
• HTTP POST requests to the plugin settings page from external referrers
• Administrator accounts showing activity at unusual times coinciding with settings changes

Detection Strategies

• Monitor WordPress audit logs for plugin settings modifications without corresponding legitimate admin activity
• Implement Web Application Firewall (WAF) rules to detect CSRF patterns targeting WordPress admin endpoints
• Review HTTP referrer headers for settings update requests originating from non-WordPress domains
• Deploy SentinelOne Singularity to detect suspicious browser-based attack chains targeting administrative sessions

Monitoring Recommendations

• Enable WordPress security plugins with CSRF detection capabilities
• Configure real-time alerting for plugin configuration changes in production environments
• Review server access logs for unusual POST requests to /wp-admin/ endpoints with external referrers
• Implement browser-level protections such as SameSite cookie attributes to reduce CSRF exposure

How to Mitigate CVE-2025-15377

Immediate Actions Required

• Deactivate and remove the Sosh Share Buttons plugin until a patched version is available
• Review current plugin settings for any unauthorized modifications
• Consider alternative social sharing plugins with proper CSRF protection
• Educate administrators about avoiding suspicious links while logged into WordPress admin

Patch Information

At the time of publication, no official patch has been released for this vulnerability. Monitor the WordPress Plugin Repository for security updates. Users are advised to check the Wordfence Vulnerability Report for the latest remediation guidance.

Workarounds

• Remove the vulnerable plugin entirely from WordPress installations
• Implement a Web Application Firewall (WAF) rule to require valid referrer headers for admin POST requests
• Use WordPress security plugins that add additional CSRF protection layers
• Restrict administrator access to trusted IP addresses to reduce attack surface

# Configuration example - WordPress .htaccess CSRF mitigation
# Add referrer validation for admin requests
<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{REQUEST_METHOD} POST
    RewriteCond %{REQUEST_URI} ^/wp-admin/
    RewriteCond %{HTTP_REFERER} !^https?://(www\.)?yourdomain\.com [NC]
    RewriteRule ^ - [F,L]
</IfModule>