CVE-2015-9393 in users-ultra Plugin
Summary
by MITRE
The users-ultra plugin before 1.5.63 for WordPress has XSS via the p_desc parameter.
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Analysis
by VulDB Data Team • 12/26/2023
The CVE-2015-9393 vulnerability affects the users-ultra plugin version 1.5.62 and earlier for WordPress, representing a cross-site scripting flaw that allows remote attackers to inject malicious scripts into web pages viewed by other users. This vulnerability specifically manifests through the p_desc parameter, which is used to handle user profile descriptions within the plugin's functionality. The issue stems from inadequate input validation and output escaping mechanisms within the plugin's codebase, creating an entry point for attackers to execute arbitrary JavaScript code in the context of affected websites.
The technical exploitation of this vulnerability occurs when an attacker crafts a malicious payload containing script code and injects it into the p_desc parameter during user profile creation or modification processes. When other users view these profiles, the malicious script executes in their browsers, potentially leading to session hijacking, credential theft, or redirection to malicious websites. The vulnerability aligns with CWE-79, which describes improper neutralization of input during web page generation, specifically categorizing it as a cross-site scripting weakness. This flaw operates at the application layer and requires no privileged access, making it particularly dangerous for widespread exploitation.
From an operational impact perspective, this vulnerability compromises the security posture of WordPress installations using the affected plugin, potentially allowing attackers to escalate privileges or gain unauthorized access to user accounts. The vulnerability affects not only the immediate users of the plugin but also the broader website ecosystem, as compromised user sessions could be leveraged for further attacks. The attack surface is expanded by the fact that the vulnerability exists in a widely used plugin, increasing the likelihood of successful exploitation across multiple sites. Organizations may experience data breaches, reputational damage, and potential compliance violations depending on the nature of user data processed through the affected plugin.
Mitigation strategies for this vulnerability include immediate patching to version 1.5.63 or later, which contains the necessary fixes to properly sanitize and escape user input. Security teams should implement input validation measures at multiple layers, including server-side sanitization of all user-provided data before processing or storage. Network monitoring should be enhanced to detect suspicious parameter values in web requests, particularly those containing script tags or unusual character sequences. The principle of least privilege should be applied by restricting plugin functionality to only necessary permissions, and regular security audits should be conducted to identify similar vulnerabilities in other installed plugins. Organizations should also consider implementing content security policies to prevent execution of unauthorized scripts, as outlined in the mitre ATT&CK framework's technique T1059 for command and scripting interpreter usage. Additionally, maintaining updated security tooling and conducting regular vulnerability assessments helps prevent exploitation of similar weaknesses in the WordPress ecosystem.