CVE-2018-12580 in vBSecurity
Summary
by MITRE
library/DBTech/Security/Action/Sessions.php in DragonByte vBSecurity 3.x through 3.3.0 for vBulletin 3 and vBulletin 4 allows self-XSS via $session['user_agent'] in the "Login Sessions" feature.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 02/20/2020
The vulnerability identified as CVE-2018-12580 resides within the DragonByte vBSecurity plugin version 3.x through 3.3.0 for vBulletin 3 and vBulletin 4 platforms. This security flaw specifically affects the library/DBTech/Security/Action/Sessions.php component and represents a self-XSS (Cross-Site Scripting) vulnerability that can be exploited through the $session['user_agent'] parameter within the "Login Sessions" feature. The vulnerability stems from insufficient input validation and output sanitization mechanisms that fail to properly escape or filter user-controllable data before rendering it in the web interface.
The technical implementation of this vulnerability occurs when the system processes session data, particularly the user agent string that is stored and displayed within the login sessions management interface. When an attacker can manipulate or inject malicious script code into the user agent field, this data is subsequently rendered back to the user without proper HTML escaping or sanitization. This creates an environment where a malicious actor can craft a user agent string containing JavaScript code that executes in the context of other administrators or users who view the session information. The vulnerability is classified as a self-XSS because the malicious payload is stored and then executed within the same application context, making it particularly dangerous for administrative interfaces where sensitive session data is displayed.
The operational impact of this vulnerability extends beyond simple script execution as it can enable attackers to perform various malicious activities including session hijacking, credential theft, and privilege escalation within the vBulletin platform. Attackers can leverage this vulnerability to inject persistent scripts that monitor user interactions, capture authentication tokens, or redirect users to malicious domains. The vulnerability affects the core security functionality of the platform by undermining the trust model of session management and potentially allowing unauthorized access to administrative controls. Given that the DragonByte vBSecurity plugin is designed to enhance security, this vulnerability creates a dangerous paradox where the security tool itself becomes a vector for exploitation.
Organizations using affected versions of vBulletin with the DragonByte vBSecurity plugin face significant risk from this vulnerability, particularly in environments where administrators frequently access session information through the web interface. The attack vector requires minimal privileges and can be executed through simple user agent manipulation, making it accessible to attackers with basic web application exploitation knowledge. Security practitioners should note that this vulnerability aligns with CWE-79 (Cross-Site Scripting) and can be mapped to ATT&CK technique T1059.007 (Command and Scripting Interpreter: JavaScript) as it enables JavaScript-based attacks. The vulnerability represents a critical weakness in input validation and output encoding practices within the application's security management components.
The recommended mitigation strategies include immediate patching of the DragonByte vBSecurity plugin to version 3.3.1 or later, which contains the necessary fixes for this XSS vulnerability. Additionally, administrators should implement proper input validation and output encoding mechanisms throughout the application, particularly for user-controllable data that is displayed in administrative interfaces. Regular security audits of third-party plugins and components should be conducted to identify similar vulnerabilities in the application ecosystem. Network monitoring should be enhanced to detect suspicious user agent strings that may indicate exploitation attempts, and security awareness training should be provided to administrators to recognize potential XSS attack patterns. The vulnerability demonstrates the importance of maintaining up-to-date security software and implementing defense-in-depth strategies that include both application-level and network-level protections against cross-site scripting attacks.