CVE-2016-7149 in b2evolution
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in b2evolution 6.7.5 and earlier allows remote attackers to inject arbitrary web script or HTML via vectors related to the autolink function.
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Analysis
by VulDB Data Team • 05/13/2026
The CVE-2016-7149 vulnerability represents a critical cross-site scripting flaw discovered in b2evolution version 6.7.5 and earlier implementations. This vulnerability specifically targets the autolink function within the content management system, creating a pathway for remote attackers to execute malicious web scripts or HTML code within the context of affected user sessions. The flaw resides in how the system processes and renders user-generated content, particularly when automatic linking of URLs and email addresses occurs during content parsing. This vulnerability type falls under the CWE-79 category of Cross-Site Scripting, which is classified as a fundamental web application security weakness that allows attackers to inject client-side scripts into web pages viewed by other users. The autolink functionality typically processes text to automatically convert URLs and email addresses into clickable hyperlinks, but in this case, insufficient input validation and output encoding creates an exploitable condition.
The operational impact of this vulnerability extends beyond simple script injection, as it enables attackers to perform a range of malicious activities including session hijacking, credential theft, data exfiltration, and redirection to malicious domains. When a user views content containing maliciously crafted input within an autolinked element, the browser executes the injected script within the victim's session context, potentially compromising the entire user experience and underlying data integrity. Attackers can leverage this vulnerability to create persistent XSS payloads that remain active across multiple user sessions, or craft targeted attacks against specific user groups within the b2evolution platform. The vulnerability is particularly concerning because it operates at the content rendering level, meaning that any user who views affected content becomes a potential victim regardless of their administrative privileges or session security measures. This aligns with the ATT&CK technique T1566.001 which describes the use of web shells and client-side attacks to establish persistent access through user interaction with malicious content.
Mitigation strategies for CVE-2016-7149 must address both immediate remediation and long-term architectural improvements to prevent similar vulnerabilities. The primary solution involves upgrading to b2evolution version 6.8.0 or later, where the autolink function has been properly patched to sanitize input parameters and implement proper output encoding. Organizations should also implement comprehensive input validation mechanisms that filter or escape special characters before processing user content, particularly focusing on the specific elements that trigger autolinking behavior. Additional defensive measures include implementing Content Security Policy headers to restrict script execution, employing Web Application Firewalls to detect and block malicious payloads, and conducting regular security assessments of user input handling functions. The vulnerability demonstrates the importance of proper sanitization of dynamic content and highlights the need for security-conscious development practices that follow secure coding guidelines such as those outlined in OWASP Top Ten and the CWE guidelines for preventing XSS vulnerabilities. Organizations should also consider implementing automated scanning tools that can detect similar patterns in custom code extensions or modifications to the core b2evolution framework that might introduce analogous security weaknesses.