CVE-2016-5313 in Web Gateway
Summary
by MITRE
Symantec Web Gateway (SWG) before 5.2.5 allows remote authenticated users to execute arbitrary OS commands.
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Analysis
by VulDB Data Team • 09/22/2022
Symantec Web Gateway version 5.2.4 and earlier contains a critical command injection vulnerability that enables authenticated remote attackers to execute arbitrary operating system commands on the affected system. This vulnerability stems from insufficient input validation and improper sanitization of user-supplied data within the web interface, specifically affecting the configuration management and logging functionalities. The flaw exists in the way the software processes user-provided parameters that are subsequently passed to underlying system commands without adequate filtering or escaping mechanisms.
The technical implementation of this vulnerability involves a classic command injection attack vector where malicious input is concatenated directly into system command strings without proper sanitization. An authenticated user can exploit this by manipulating specific parameters in the web administration interface, particularly those related to log file management, network configuration, or system monitoring features. The vulnerability is categorized under CWE-77 as "Improper Neutralization of Special Elements used in a Command ('Command Injection')", which is a well-documented weakness that has been consistently exploited across various network security appliances and web applications. This weakness directly maps to several techniques described in the MITRE ATT&CK framework under T1059.001 for Command and Scripting Interpreter and T1068 for Exploitation for Privilege Escalation.
The operational impact of this vulnerability is severe and multifaceted, as it provides attackers with full system-level access to the Symantec Web Gateway appliance. Once exploited, an attacker can execute arbitrary commands with the privileges of the web server process, typically running with elevated system permissions. This access enables the attacker to modify configurations, extract sensitive data, establish persistence mechanisms, and potentially use the compromised appliance as a pivot point to attack other systems within the network. The vulnerability affects the confidentiality, integrity, and availability of the entire security infrastructure, as the compromised appliance can no longer be trusted to properly filter network traffic or enforce security policies. Network administrators may also face challenges in detecting the compromise due to the legitimate nature of command execution through the web interface.
Organizations should immediately implement mitigations including upgrading to Symantec Web Gateway version 5.2.5 or later, which contains the necessary patches to address the command injection vulnerability. Additionally, network segmentation and access controls should be enforced to limit administrative access to the web gateway interface, reducing the attack surface. Implementing proper input validation and output encoding mechanisms within the web application framework can help prevent similar issues in the future. Security monitoring should include detection of unusual command execution patterns and anomalous administrative activities within the web gateway logs. Regular security assessments and vulnerability scanning should be conducted to identify and remediate similar weaknesses in other network security appliances. The remediation process should also include reviewing and updating security policies to ensure proper administrative access controls and monitoring procedures are in place to prevent unauthorized access to critical network infrastructure components.