CVE-2010-4402 in Register-plus
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in wp-login.php in the Register Plus plugin 3.5.1 and earlier for WordPress allow remote attackers to inject arbitrary web script or HTML via the (1) firstname, (2) lastname, (3) website, (4) aim, (5) yahoo, (6) jabber, (7) about, (8) pass1, and (9) pass2 parameters in a register action.
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Analysis
by VulDB Data Team • 09/03/2017
The vulnerability identified as CVE-2010-4402 represents a critical cross-site scripting weakness within the Register Plus plugin for WordPress systems. This flaw affects versions 3.5.1 and earlier, creating a significant security risk for WordPress installations that utilize this plugin. The vulnerability resides in the wp-login.php file which processes user registration requests and fails to properly sanitize user input parameters, allowing malicious actors to inject malicious scripts into the registration flow. The specific parameters that exhibit this vulnerability include firstname, lastname, website, aim, yahoo, jabber, about, pass1, and pass2 fields, all of which are commonly used during user registration processes on WordPress platforms.
From a technical perspective, this vulnerability manifests as a classic reflected cross-site scripting attack vector where unfiltered user input is directly incorporated into the web page response without proper HTML encoding or validation. The CWE-79 classification applies here, as the vulnerability represents a failure to sanitize user-supplied data before incorporating it into dynamically generated web content. The attack occurs when a malicious user submits crafted script code through any of the vulnerable parameters during the registration process, which then gets executed in the context of other users' browsers who view the affected registration data. This creates a persistent threat where the malicious code can steal session cookies, redirect users to phishing sites, or perform other malicious actions on behalf of the victims.
The operational impact of this vulnerability extends beyond simple data corruption or display issues, as it enables attackers to compromise the entire WordPress user registration ecosystem. When exploited, these XSS vulnerabilities can lead to session hijacking, where attackers steal user authentication tokens and gain unauthorized access to user accounts. The attack vector is particularly dangerous because it targets the registration page itself, which is frequently accessed by both legitimate users and potential attackers. This creates an environment where even users who are not directly targeted can become victims when they view registration data containing malicious scripts. The vulnerability also aligns with ATT&CK technique T1566.002, which describes the use of credential harvesting through web-based attacks, making it a significant threat to user authentication security.
Mitigation strategies for this vulnerability require immediate action including updating to the latest version of the Register Plus plugin where the XSS issues have been resolved through proper input sanitization and output encoding. System administrators should implement comprehensive input validation mechanisms that strip or encode potentially dangerous characters before processing user data. The implementation of Content Security Policy headers can provide additional protection by preventing the execution of unauthorized scripts in the browser context. Regular security audits of WordPress plugins and themes are essential to identify similar vulnerabilities, as this type of flaw demonstrates the importance of proper data sanitization in web applications. Organizations should also consider implementing web application firewalls to detect and block suspicious input patterns, and maintain updated security monitoring systems to identify potential exploitation attempts. The vulnerability serves as a reminder that even seemingly benign registration forms can become attack vectors when proper security measures are not implemented in the code.