CVE-2025-13627: Makesweat WordPress Plugin XSS Flaw

CVE-2025-13627 Overview

The Makesweat plugin for WordPress is vulnerable to Stored Cross-Site Scripting (XSS) via the makesweat_clubid setting in all versions up to, and including, 0.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Critical Impact

Authenticated administrators can inject malicious JavaScript that persists in the database and executes in the browser context of any user viewing affected pages, potentially leading to session hijacking, credential theft, or administrative account compromise.

Affected Products

• Makesweat WordPress Plugin version 0.1 and earlier
• WordPress sites with Makesweat plugin installed and active

Discovery Timeline

• 2026-01-14 - CVE-2025-13627 published to NVD
• 2026-01-14 - Last updated in NVD database

Technical Details for CVE-2025-13627

Vulnerability Analysis

This Stored Cross-Site Scripting vulnerability exists in the Makesweat WordPress plugin due to improper handling of the makesweat_clubid setting. The plugin fails to properly sanitize user input before storing it in the database and does not adequately escape the output when rendering this setting value on pages. When an authenticated administrator with sufficient privileges modifies this setting, they can inject arbitrary JavaScript code that will be stored and subsequently executed in the browsers of users who visit pages where this setting value is rendered.

The vulnerability requires network access and high-privilege authentication (administrator level), which limits the attack surface. However, in multi-administrator environments or scenarios where an attacker has already compromised an admin account, this vulnerability could be leveraged for further attacks against other administrators or site visitors.

Root Cause

The root cause is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation). The vulnerable code, located in makesweat.php at lines 64 and 85, fails to implement proper input validation and output encoding. The makesweat_clubid setting value is accepted without sufficient sanitization when saved and rendered without proper escaping when displayed, allowing JavaScript code to be injected and executed.

Attack Vector

The attack is conducted over the network and requires the attacker to have authenticated administrator-level access to the WordPress installation. The attacker would navigate to the plugin settings page and insert malicious JavaScript code into the makesweat_clubid field. Once saved, this payload is stored in the WordPress database.

When any user (including other administrators) accesses a page where the makesweat_clubid value is rendered, the malicious script executes in their browser context. This could allow the attacker to steal session cookies, perform actions on behalf of the victim, redirect users to malicious sites, or deface the website content.

The vulnerability mechanism involves insufficient input sanitization when the setting is saved and improper output escaping when the value is displayed. For detailed code analysis, see the WordPress Plugin Source Code and the Wordfence Vulnerability Report.

Detection Methods for CVE-2025-13627

Indicators of Compromise

• Suspicious JavaScript code present in the makesweat_clubid option value in the WordPress database
• Unusual administrator activity or setting changes in WordPress audit logs
• Unexpected inline scripts or event handlers appearing on pages where the Makesweat plugin renders content
• Reports of browser security warnings or anomalous behavior from site visitors

Detection Strategies

• Review the wp_options table for the makesweat_clubid entry and check for any HTML or JavaScript content
• Implement Content Security Policy (CSP) headers to detect and block unauthorized inline script execution
• Deploy a Web Application Firewall (WAF) configured to detect XSS patterns in POST requests to the plugin settings
• Utilize WordPress security plugins that monitor option value changes for suspicious content

Monitoring Recommendations

• Enable comprehensive WordPress audit logging to track all administrator actions and plugin setting modifications
• Configure real-time alerts for changes to the Makesweat plugin settings
• Implement client-side monitoring for unexpected script execution using browser-based security tools
• Regularly audit WordPress database option values for potential malicious payloads

How to Mitigate CVE-2025-13627

Immediate Actions Required

• Review and audit all administrator accounts for unauthorized access or compromise
• Inspect the current value of makesweat_clubid in the WordPress options table for any malicious content
• Consider temporarily deactivating the Makesweat plugin until a patched version is available
• Implement additional access controls to limit administrator privileges where possible

Patch Information

As of the last NVD update on 2026-01-14, no official patch has been confirmed for this vulnerability. Users should monitor the WordPress Plugin Overview page for updates from the plugin developer. If a patched version becomes available, update immediately to remediate this vulnerability.

Workarounds

• Deactivate and remove the Makesweat plugin if it is not critical to site functionality
• Implement a Web Application Firewall (WAF) rule to sanitize input to the makesweat_clubid setting
• Restrict administrator access to only trusted users and implement strong authentication measures
• Manually sanitize the makesweat_clubid option value in the database by removing any HTML or script content

# WordPress CLI command to check the current value of makesweat_clubid
wp option get makesweat_clubid

# If malicious content is found, reset the option to a safe value
wp option update makesweat_clubid "YOUR_SAFE_CLUB_ID"