CVE-2025-11162 is a stored Cross-Site Scripting (XSS) vulnerability classified under CWE-79, found in the Spectra Gutenberg Blocks – Website Builder for the Block Editor plugin for WordPress. This vulnerability arises from improper neutralization of input during web page generation, specifically in the handling of Custom CSS inputs. Versions up to and including 2.19.14 fail to adequately sanitize and escape user-supplied CSS, allowing authenticated users with Contributor-level access or higher to inject arbitrary JavaScript code. Because the malicious script is stored persistently within the website content, it executes whenever any user accesses the infected page, potentially compromising user sessions, stealing cookies, or performing unauthorized actions on behalf of users. The vulnerability requires no user interaction beyond visiting the affected page and does not require elevated privileges beyond Contributor access, which is commonly granted to many users in collaborative WordPress environments. The CVSS 3.1 score of 6.4 reflects a medium severity, with network attack vector, low attack complexity, and partial impact on confidentiality and integrity but no impact on availability. No known public exploits have been reported yet, but the vulnerability poses a significant risk to websites relying on this plugin for content creation and styling. The lack of a patch at the time of reporting necessitates immediate risk mitigation steps by administrators.

For European organizations, this vulnerability can lead to unauthorized script execution on their WordPress sites, potentially resulting in session hijacking, data theft, defacement, or distribution of malware to site visitors. Organizations with collaborative content management workflows that grant Contributor or higher access to multiple users are particularly vulnerable. The compromise of user credentials or site integrity could damage brand reputation, lead to regulatory compliance issues under GDPR due to data breaches, and cause operational disruptions. Since WordPress powers a significant portion of European websites, especially in small and medium enterprises, the attack surface is substantial. Attackers exploiting this vulnerability could target government portals, e-commerce platforms, and corporate websites, leading to broader security incidents. The medium severity rating indicates a moderate but actionable risk that requires prompt attention to prevent exploitation.

1. Immediately restrict Contributor-level user permissions to trusted individuals only and review existing user roles for unnecessary privileges. 2. Disable or restrict the use of the Custom CSS feature in the Spectra Gutenberg Blocks plugin until a security patch is released. 3. Implement Web Application Firewall (WAF) rules to detect and block suspicious script injection attempts targeting Custom CSS inputs. 4. Monitor website content for unexpected or unauthorized script tags or suspicious CSS entries. 5. Educate content contributors about the risks of injecting untrusted code and enforce strict content review policies. 6. Once available, promptly apply the official security patch or update the plugin to a fixed version. 7. Employ Content Security Policy (CSP) headers to limit the execution of inline scripts and reduce the impact of potential XSS attacks. 8. Regularly audit WordPress plugins and themes for vulnerabilities and maintain an up-to-date inventory of installed components.