CVE-2025-66066 in Envo Extra Plugin
Summary
by MITRE • 11/21/2025
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in EnvoThemes Envo Extra envo-extra allows Stored XSS.This issue affects Envo Extra: from n/a through <= 1.9.11.
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Analysis
by VulDB Data Team • 11/22/2025
The vulnerability identified as CVE-2025-66066 represents a critical cross-site scripting flaw within the EnvoThemes Envo Extra plugin, specifically impacting versions through 1.9.11. This weakness falls under the category of improper input neutralization during web page generation, creating a persistent security risk that allows attackers to inject malicious scripts into web pages viewed by other users. The vulnerability specifically enables stored cross-site scripting attacks, meaning that malicious code can be permanently stored on the server and subsequently executed whenever affected pages are loaded by unsuspecting users. This type of vulnerability is particularly dangerous because it can remain dormant for extended periods while continuously affecting visitors to compromised websites.
The technical flaw manifests in how the Envo Extra plugin processes user input within its web page generation routines, failing to adequately sanitize or escape data before rendering it in HTML output contexts. When users submit content through forms or other interactive elements within the plugin interface, the system does not properly validate or encode the input data, allowing potentially malicious scripts to be stored in the database and later executed in the browsers of other users. This represents a classic stored XSS vulnerability pattern where the malicious payload is stored server-side rather than being reflected in a single request, making it more persistent and harder to detect. The vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws in web applications, and demonstrates how inadequate input validation and output encoding can create dangerous security exposures in content management systems.
The operational impact of this vulnerability extends beyond simple script execution, as it provides attackers with the ability to hijack user sessions, steal sensitive cookies, perform unauthorized actions on behalf of victims, and potentially gain complete control over compromised user accounts. Attackers can exploit this weakness to redirect users to malicious websites, harvest login credentials, or inject additional malicious payloads that could lead to further compromise of the affected website. The stored nature of this XSS vulnerability means that even users who do not interact directly with the vulnerable plugin interface can be affected, as the malicious code executes automatically when pages containing the stored content are loaded. This vulnerability directly impacts the integrity and confidentiality of web applications, potentially compromising the security posture of entire websites that rely on the affected plugin. Organizations using this plugin face significant risk of data breaches, unauthorized access, and potential regulatory compliance violations.
Mitigation strategies for CVE-2025-66066 should prioritize immediate patching of the Envo Extra plugin to the latest version that addresses this vulnerability, as recommended by the plugin vendor. System administrators should implement comprehensive input validation and output encoding measures across all user-submitted content, ensuring that any data entering the system is properly sanitized before storage. The implementation of Content Security Policy headers can provide additional defense-in-depth protection against XSS attacks by restricting script execution contexts. Regular security audits and vulnerability assessments should be conducted to identify similar weaknesses in other plugins or components of the web application stack. Organizations should also consider implementing web application firewalls and monitoring systems to detect and prevent exploitation attempts. This vulnerability demonstrates the critical importance of maintaining up-to-date software components and implementing robust security practices throughout the application development lifecycle, as outlined in various cybersecurity frameworks including those referenced in the ATT&CK framework for web application security threats.