CVE-2026-1825 in Show YouTube Video Plugin
Summary
by MITRE • 03/07/2026
The Show YouTube video plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'syv' shortcode in all versions up to, and including, 1.1 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 • 03/08/2026
The vulnerability identified as CVE-2026-1825 affects the Show YouTube video plugin for WordPress, representing a critical stored cross-site scripting weakness that has persisted across all versions up to and including 1.1. This flaw resides within the plugin's 'syv' shortcode implementation where inadequate input sanitization and output escaping mechanisms fail to properly validate or escape user-supplied attributes. The vulnerability's classification as a stored XSS issue means that malicious scripts injected through this vector can persist in the application's database and execute whenever affected pages are accessed by unsuspecting users. The security implications are particularly severe given that the vulnerability can be exploited by authenticated attackers who possess contributor-level access or higher, which represents a relatively low barrier to exploitation within typical WordPress environments where such roles are often assigned to users with varying degrees of trust.
The technical exploitation of this vulnerability occurs through the manipulation of the 'syv' shortcode attributes, where user input is directly incorporated into the plugin's output without proper sanitization measures. This creates a persistent attack vector where malicious code can be stored in the WordPress database and subsequently executed in the context of other users' browsers. The flaw demonstrates a clear violation of secure coding practices, specifically relating to input validation and output encoding as defined by the CWE-79 weakness classification for cross-site scripting vulnerabilities. Attackers can leverage this vulnerability to execute arbitrary JavaScript code within the browser context of authenticated users, potentially leading to session hijacking, data exfiltration, or further compromise of the WordPress installation.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to establish persistent footholds within WordPress environments. Since the vulnerability requires only contributor-level access, it can be exploited by users who have legitimate editing privileges, making it particularly dangerous in multi-user environments where contributor roles are commonly assigned. The stored nature of the vulnerability means that once a malicious payload is injected, it will continue to execute for all users who access the affected pages, creating a widespread potential for damage. This type of vulnerability aligns with ATT&CK technique T1566.002 for credential access through social engineering, as attackers can craft payloads that appear legitimate while executing malicious code. The impact is particularly concerning for organizations that rely on WordPress for content management, as the vulnerability could be used to compromise user sessions, steal sensitive information, or perform unauthorized administrative actions.
Mitigation strategies for this vulnerability should focus on immediate remediation through plugin updates to versions that address the input sanitization and output escaping issues. Organizations should implement comprehensive access control measures, ensuring that only trusted users have contributor-level privileges, while also applying additional security layers such as web application firewalls that can detect and block malicious payloads. The vulnerability highlights the critical importance of proper input validation and output encoding practices in web application development, particularly for plugins that handle user-supplied content. Regular security audits of WordPress plugins, including vulnerability scanning and code review processes, should be implemented to identify similar weaknesses before they can be exploited. Additionally, administrators should consider implementing content security policies and monitoring for suspicious shortcode usage patterns that might indicate exploitation attempts. The vulnerability serves as a reminder of the necessity for robust security practices in WordPress plugin development, emphasizing the need for adherence to security standards such as those outlined in the OWASP Top Ten and other industry best practices for preventing cross-site scripting vulnerabilities.