CVE-2026-66663 in Data Access Plugin
Summary
by MITRE • 08/06/2026
Unauthenticated Cross Site Scripting (XSS) in WP Data Access <= 5.5.79 versions.
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Analysis
by VulDB Data Team • 08/06/2026
The vulnerability identified as unauthenticated cross site scripting in WP Data Access plugin versions up to 5.5.79 represents a critical security flaw that allows attackers to execute malicious scripts in the context of a victim's browser without requiring authentication credentials. This issue stems from insufficient input validation and output sanitization within the plugin's codebase, creating an avenue for persistent script injection attacks that can compromise user sessions and data integrity.
The technical implementation of this vulnerability occurs through improper handling of user-supplied data within the plugin's administrative interfaces and frontend components. When users interact with data display functionalities or administrative forms, the plugin fails to adequately sanitize or escape output rendered to web browsers, enabling attackers to inject malicious javascript code that executes in the context of legitimate user sessions. This flaw aligns with CWE-79 - Improper Neutralization of Input During Web Page Generation, which specifically addresses the failure to properly sanitize input data before incorporating it into dynamic web content.
The operational impact of this vulnerability extends beyond simple script execution as it can enable attackers to perform session hijacking, steal sensitive cookies, redirect users to malicious domains, or even modify database content through sophisticated attack vectors. Attackers can leverage this weakness by crafting specially formatted requests that bypass authentication mechanisms entirely, exploiting the plugin's lack of proper access controls for data manipulation functions. The vulnerability affects all users who have the WP Data Access plugin installed regardless of their authentication status, making it particularly dangerous in multi-user environments.
Security professionals should implement immediate mitigations including disabling or uninstalling affected plugin versions until patches are available, implementing web application firewalls to detect and block malicious script injection attempts, and conducting thorough code reviews of all user input handling within the WordPress installation. Organizations should also consider deploying content security policies to limit script execution contexts and monitor for suspicious activities in their web application logs. This vulnerability demonstrates the importance of proper input validation practices and aligns with ATT&CK technique T1566.001 - Phishing: Spearphishing Attachment, as attackers can craft malicious payloads that appear legitimate within the context of data display interfaces.
The broader implications highlight the need for comprehensive security testing of WordPress plugins, particularly those handling user data or providing administrative functions. Regular vulnerability assessments should include testing for common web application flaws such as XSS vulnerabilities, and developers should follow secure coding practices including proper output encoding, input validation, and access control mechanisms. Organizations implementing WordPress solutions must maintain updated plugin inventories and establish rapid response procedures for addressing security advisories to prevent exploitation of known vulnerabilities in their web applications.
Additional defensive measures include implementing proper logging and monitoring of administrative activities, establishing regular security audits of third-party plugins, and maintaining up-to-date security patches across all WordPress components. The vulnerability underscores the importance of defense-in-depth strategies that combine multiple security controls to protect against various attack vectors while ensuring that plugin developers follow industry standards such as OWASP Top Ten guidelines for secure web application development practices.