CVE-2012-2633 in WassUp plugin
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in wassup.php in the WassUp plugin before 1.8.3.1 for WordPress allows remote attackers to inject arbitrary web script or HTML via the User-Agent HTTP header.
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Analysis
by VulDB Data Team • 01/16/2018
The CVE-2012-2633 vulnerability represents a classic cross-site scripting flaw within the WassUp plugin for WordPress systems. This security weakness specifically affects versions prior to 1.8.3.1 and demonstrates how seemingly innocuous HTTP header parameters can become attack vectors for malicious code execution. The vulnerability resides in the wassup.php file which processes user agent information without proper input sanitization, creating an opportunity for remote attackers to inject arbitrary web scripts or HTML content. The attack surface is particularly concerning as it leverages the User-Agent HTTP header, a standard component of web requests that is typically not considered a primary attack vector by security practitioners.
The technical exploitation of this vulnerability occurs when an attacker crafts a malicious User-Agent string containing script code that gets processed and stored within the WordPress plugin's data handling mechanisms. When other users view the affected plugin interface or reports, their browsers execute the injected malicious scripts, potentially leading to session hijacking, credential theft, or redirection to malicious sites. This XSS implementation follows the CWE-79 pattern of insecure direct object reference and aligns with ATT&CK technique T1566.001 for initial access through spearphishing attachments or links. The flaw demonstrates poor input validation practices where the plugin fails to properly escape or sanitize user-supplied data before it is rendered in the web interface.
The operational impact of CVE-2012-2633 extends beyond simple script injection, as it provides attackers with persistent access to affected WordPress installations. Once exploited, attackers can establish backdoors, modify content, steal administrator credentials, or deploy additional malware through the compromised plugin. The vulnerability affects the integrity of the WordPress admin interface and can lead to complete system compromise if administrators are tricked into viewing malicious reports. This issue particularly impacts small to medium businesses that rely on WordPress plugins for analytics and security monitoring, as the WassUp plugin is commonly used for tracking visitor information. The vulnerability can be exploited through automated scanning tools that probe for common WordPress plugin weaknesses, making it a frequent target in large-scale attacks.
Mitigation strategies for CVE-2012-2633 require immediate patching of the WassUp plugin to version 1.8.3.1 or later, which implements proper input sanitization and output encoding. Administrators should also implement additional security measures including web application firewalls that can detect and block malicious User-Agent patterns, regular security audits of installed plugins, and monitoring of plugin-related database entries for suspicious activity. The vulnerability highlights the importance of input validation at multiple layers and demonstrates why CWE-116 and CWE-20 should be considered during plugin development. Organizations should also consider implementing Content Security Policy headers to prevent execution of unauthorized scripts, and establish procedures for regular plugin updates and security assessments. The ATT&CK framework suggests that this vulnerability could be detected through behavioral monitoring of unusual HTTP header patterns and anomalous data processing within web applications.