Overview
This article details CVE-2025-66091, a DOM-Based Cross-Site Scripting (XSS) vulnerability affecting the Stylish Cost Calculator WordPress plugin. This vulnerability allows attackers to inject malicious scripts into web pages viewed by users, potentially leading to data theft, session hijacking, or website defacement. The affected plugin versions are up to and including 8.1.5.
Technical Details of CVE-2025-66091
CVE-2025-66091 is a DOM-Based XSS vulnerability. This means the malicious script doesn’t directly interact with the server. Instead, the vulnerability lies in the client-side JavaScript code of the Stylish Cost Calculator plugin. The plugin improperly neutralizes user-supplied input during the generation of web pages, allowing an attacker to inject malicious JavaScript code through crafted URLs or other input fields that are then processed by the client-side script. This input is then executed in the victim’s browser, allowing the attacker to perform actions on behalf of the user.
CVSS Analysis
Currently, the CVSS score is listed as N/A. However, given the nature of XSS vulnerabilities, the impact could be significant depending on the context. While the score is unavailable, XSS vulnerabilities are generally considered to be of medium to high severity, potentially allowing for account takeover and other malicious activities.
Possible Impact
Exploitation of this XSS vulnerability can lead to:
- Account Takeover: An attacker could steal a user’s session cookie and hijack their account.
- Website Defacement: Malicious scripts can modify the content of the website, defacing it or displaying misleading information.
- Data Theft: Sensitive information entered by users on the affected pages could be stolen and sent to the attacker.
- Malware Distribution: The attacker could inject scripts that redirect users to malicious websites or attempt to install malware on their systems.
Mitigation and Patch Steps
To protect your website from CVE-2025-66091, take the following steps:
- Update the Plugin: The most critical step is to update the Stylish Cost Calculator plugin to the latest version as soon as a patch is released. Check the WordPress plugin repository for updates.
- Web Application Firewall (WAF): Implement a Web Application Firewall (WAF) to filter out malicious requests and protect against XSS attacks. Many WordPress security plugins offer WAF functionality.
- Input Validation and Output Encoding: While awaiting a patch, consider if temporary measures can be implemented (with caution). Validate all user inputs on both the client-side and server-side. Encode output properly to prevent the execution of malicious scripts. This requires technical expertise and should be done carefully.
- Regular Security Audits: Conduct regular security audits of your WordPress website and plugins to identify and address potential vulnerabilities.
