CVE-2016-2046 in UTM
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in the Nessus Web UI in SOPHOS UTM before 9.353 allows remote attackers to inject arbitrary web script or HTML via the lang parameter.
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Analysis
by VulDB Data Team • 07/08/2022
The vulnerability identified as CVE-2016-2046 represents a critical cross-site scripting flaw within the Nessus Web User Interface component of SOPHOS UTM versions prior to 9.353. This weakness resides in the application's handling of the lang parameter, which is used to determine the language interface for the web-based management console. The vulnerability enables remote attackers to execute malicious scripts within the context of other users' browsers, potentially leading to unauthorized access to sensitive information or system compromise. The flaw specifically manifests when the application fails to properly sanitize user input passed through the lang parameter, allowing attackers to inject arbitrary HTML and JavaScript code that gets executed in the victim's browser session.
This vulnerability falls under the CWE-79 category of Cross-Site Scripting, which is classified as a critical weakness in web application security. The attack vector leverages the web application's insufficient input validation and output encoding mechanisms. When a user navigates to a maliciously crafted URL containing the XSS payload within the lang parameter, the web interface processes this input without proper sanitization, subsequently rendering the malicious code within the browser context. The ATT&CK framework categorizes this as a Web Application Attack technique under the T1059.007 sub-technique for Scripting, where adversaries leverage web application vulnerabilities to execute malicious code in victim browsers.
The operational impact of this vulnerability extends beyond simple script injection, as it can enable attackers to perform session hijacking, steal authentication tokens, access sensitive configuration data, or redirect users to malicious websites. An attacker could craft a phishing link that appears legitimate but contains malicious JavaScript in the lang parameter, potentially compromising multiple users who access the vulnerable UTM system. The vulnerability is particularly concerning in enterprise environments where UTM appliances serve as central security gateways, as compromise of the web interface could provide attackers with access to network monitoring data, firewall rules, and other critical security configurations. The lack of proper input validation in the language parameter handling represents a fundamental security flaw that undermines the integrity of the web application's user interface.
Mitigation strategies for CVE-2016-2046 involve immediate patching of the SOPHOS UTM appliance to version 9.353 or later, which includes proper input sanitization for the lang parameter. Organizations should also implement additional defensive measures such as web application firewalls that can detect and block suspicious parameter values, regular security assessments of web interfaces, and input validation controls that enforce strict parameter filtering. Network segmentation and access control measures should be implemented to limit exposure of the vulnerable web interface to untrusted networks. Security monitoring should be enhanced to detect unusual patterns in web interface access, particularly around language parameter usage, and incident response procedures should be updated to address potential exploitation attempts. The vulnerability demonstrates the critical importance of proper input validation and output encoding in web applications, aligning with security best practices outlined in OWASP Top Ten and NIST Cybersecurity Framework guidelines for web application security.