CVE-2025-23636: My Favorite Car Plugin XSS Vulnerability

CVE-2025-23636 Overview

CVE-2025-23636 is a Reflected Cross-Site Scripting (XSS) vulnerability affecting the My Favorite Car WordPress plugin developed by Dimitar A. The vulnerability arises from improper neutralization of user-supplied input during web page generation, allowing attackers to inject malicious scripts that execute in the context of a victim's browser session.

Reflected XSS attacks occur when an application includes unvalidated and unescaped user input as part of HTML output. In this case, the My Favorite Car plugin fails to properly sanitize input parameters before reflecting them back to users, enabling attackers to craft malicious URLs that execute arbitrary JavaScript code when clicked by unsuspecting victims.

Critical Impact

Attackers can execute arbitrary JavaScript in victims' browsers, potentially leading to session hijacking, credential theft, defacement, or malware distribution through compromised WordPress sites.

Affected Products

• My Favorite Car WordPress Plugin version 1.0 and earlier
• WordPress installations using the my-favorite-cars plugin

Discovery Timeline

• 2025-01-23 - CVE-2025-23636 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2025-23636

Vulnerability Analysis

This vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation), which encompasses all forms of Cross-Site Scripting attacks. The My Favorite Car plugin does not adequately validate or encode user-controlled input before incorporating it into the HTML response sent to browsers.

When a user visits a crafted URL containing malicious JavaScript payload, the plugin processes the request and reflects the unsanitized input directly into the page output. The victim's browser then interprets this injected content as legitimate code and executes it with full access to the page's Document Object Model (DOM), cookies, and session data.

The attack requires user interaction—specifically, the victim must click a malicious link or visit a compromised page that redirects to the vulnerable endpoint. However, social engineering techniques can make such attacks highly effective, especially when targeting administrators of WordPress sites.

Root Cause

The root cause of this vulnerability is the absence of proper input validation and output encoding in the My Favorite Car plugin. WordPress provides built-in sanitization functions such as esc_html(), esc_attr(), and wp_kses() that should be applied to all user-supplied data before rendering it in HTML context. The plugin's failure to implement these security controls allows malicious payloads to pass through unmodified and execute in the browser.

Attack Vector

The attack is network-based and requires no authentication to exploit. An attacker constructs a URL containing a JavaScript payload targeting a vulnerable parameter in the My Favorite Car plugin. This malicious URL can be distributed via phishing emails, social media, or embedded in other websites.

When a logged-in WordPress administrator clicks the link, the injected script executes with their privileges, potentially allowing the attacker to:

• Steal session cookies and authentication tokens
• Perform administrative actions on behalf of the victim
• Inject persistent backdoors into the WordPress installation
• Redirect users to malicious websites
• Deface the website content

The attack flow typically involves crafting a URL with an XSS payload in a vulnerable GET parameter, then tricking an authenticated user into visiting that URL. The plugin reflects the payload without sanitization, and the malicious script executes in the victim's browser context.

Detection Methods for CVE-2025-23636

Indicators of Compromise

• Suspicious URL patterns in web server logs containing encoded JavaScript or HTML tags in query parameters
• Unexpected outbound requests from client browsers to unknown domains
• Reports of users experiencing unexpected redirects or pop-ups when using the affected plugin
• Unusual administrative actions in WordPress audit logs that correlate with users clicking external links

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block common XSS payload patterns in URL parameters
• Monitor HTTP request logs for suspicious characters and encoded payloads such as <script>, javascript:, onerror=, and similar XSS vectors
• Deploy browser-side Content Security Policy (CSP) headers to prevent execution of inline scripts from untrusted sources
• Use automated vulnerability scanners to test for reflected XSS in WordPress plugins

Monitoring Recommendations

• Enable detailed logging for the My Favorite Car plugin and WordPress core to capture all incoming requests
• Set up alerts for HTTP requests containing common XSS indicators in the query string or POST body
• Regularly review WordPress plugin installations for outdated or abandoned plugins that may contain similar vulnerabilities
• Monitor for unusual JavaScript execution patterns or DOM modifications using browser developer tools during security assessments

How to Mitigate CVE-2025-23636

Immediate Actions Required

• Remove or deactivate the My Favorite Car (my-favorite-cars) WordPress plugin immediately until a patched version is available
• Review web server access logs for evidence of exploitation attempts targeting this vulnerability
• Implement a Web Application Firewall with XSS protection rules as an additional layer of defense
• Audit other installed WordPress plugins for similar input validation weaknesses

Patch Information

As of the last update, the vulnerability affects My Favorite Car version 1.0 and earlier. No official patch has been referenced in the available CVE data. Site administrators should monitor the Patchstack Vulnerability Report for updates regarding a security fix from the plugin developer.

Given the plugin's limited functionality scope, consider whether the plugin is essential to site operations. If not critical, permanent removal is recommended as the safest mitigation approach.

Workarounds

• Disable the My Favorite Car plugin entirely via the WordPress admin panel under Plugins > Installed Plugins
• If the plugin must remain active, implement server-side URL filtering to block requests containing suspicious characters in known vulnerable parameters
• Deploy Content Security Policy headers to restrict inline script execution: Content-Security-Policy: default-src 'self'; script-src 'self'
• Use a WordPress security plugin that provides real-time XSS protection and virtual patching capabilities

SentinelOne Singularity provides comprehensive protection against web-based attacks including XSS exploitation attempts. The platform's behavioral AI can detect and block malicious script injection attempts in real-time, while the Storyline technology provides full attack chain visibility for forensic analysis. Organizations using SentinelOne benefit from automated threat response that can isolate compromised endpoints before attackers can leverage stolen credentials or session tokens.