CVE-2024-4193 in Testimonial Slider Plugin
Summary
by MITRE • 05/14/2024
The Testimonial Slider plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'testimonialcategory' shortcode in all versions up to, and including, 1.3.2 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
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Analysis
by VulDB Data Team • 04/01/2025
The Testimonial Slider plugin for WordPress presents a critical stored cross-site scripting vulnerability that affects all versions up to and including 1.3.2. This security flaw resides within the 'testimonialcategory' shortcode implementation where insufficient input sanitization and output escaping mechanisms fail to properly validate user-supplied attributes. The vulnerability represents a significant risk as it allows authenticated attackers with contributor-level permissions or higher to inject malicious web scripts into the plugin's functionality.
The technical nature of this flaw stems from inadequate parameter validation within the shortcode processing logic. When users with appropriate privileges create or modify testimonials using the 'testimonialcategory' shortcode, the plugin fails to sanitize the input parameters before storing them in the database. This stored malicious content then executes whenever any user accesses pages containing the vulnerable shortcode, creating a persistent XSS vector that can affect all visitors regardless of their permission level.
From an operational perspective, this vulnerability creates a dangerous attack surface for WordPress administrators and site owners. The attacker need only possess contributor-level access to exploit this weakness, which is often granted to trusted users or content creators who may not be security-aware. Once exploited, the malicious scripts can perform various harmful actions including stealing user session cookies, redirecting visitors to malicious sites, defacing the website content, or even executing arbitrary commands on the server if additional vulnerabilities exist. The stored nature of this XSS means that the malicious payload persists in the database and will continue to execute until manually removed or the plugin is updated.
The vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws in web applications, and represents a clear violation of secure coding practices for input validation and output escaping. From an ATT&CK framework perspective, this weakness maps to T1566.001 - Phishing via Social Engineering and T1203 - Exploitation for Client Execution, as it enables attackers to execute malicious code through social engineering techniques or by exploiting the trust relationships inherent in WordPress contributor roles. The impact extends beyond simple script execution as it can serve as a foothold for more sophisticated attacks including credential theft, data exfiltration, and potential privilege escalation within the affected WordPress environment.
Organizations should immediately implement mitigations including updating to the latest plugin version if available, implementing strict input validation at the application level, and considering temporary removal of the vulnerable shortcode functionality. Additionally, administrators should monitor user accounts with contributor-level access for suspicious activity and consider implementing additional security measures such as web application firewalls or content security policies to further protect against exploitation attempts. Regular security audits and penetration testing should also be conducted to identify similar vulnerabilities in other plugins or themes that may present similar risks.