CVE-2016-10256 in ProxySG
Summary
by MITRE
The Symantec ProxySG 6.5 (prior to 6.5.10.6), 6.6, and 6.7 (prior to 6.7.2.1) management console is susceptible to a reflected XSS vulnerability. A remote attacker can use a crafted management console URL in a phishing attack to inject arbitrary JavaScript code into the management console web client application. This is a separate vulnerability from CVE-2016-10257.
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Analysis
by VulDB Data Team • 01/29/2021
The Symantec ProxySG series represents a critical component in enterprise network security infrastructure, providing web proxy and content filtering services that protect organizations from malicious internet traffic. These appliances are widely deployed in corporate environments where they serve as gateways for web traffic, implementing security policies and monitoring user activity. The management console interface, which allows administrators to configure and monitor the proxy services, becomes a prime target for attackers seeking to compromise the security posture of the entire network. The vulnerability in question specifically affects versions 6.5 prior to 6.5.10.6, 6.6, and 6.7 prior to 6.7.2.1, indicating a widespread issue across multiple release branches of the software. This reflects a significant gap in the security implementation that could potentially affect numerous enterprise deployments.
The technical flaw manifests as a reflected cross-site scripting vulnerability within the management console's web interface. This type of vulnerability occurs when user-supplied input is directly reflected back in the application's response without proper sanitization or encoding. In this case, a remote attacker can craft a malicious URL containing JavaScript code and deliver it to a victim through phishing campaigns or other social engineering techniques. When an administrator clicks on the malicious link, the JavaScript code executes within the context of the management console, potentially allowing attackers to steal session cookies, modify configuration settings, or perform unauthorized administrative actions. The reflected nature of this vulnerability means that the malicious payload is not stored on the server but is instead delivered through the HTTP response, making it particularly challenging to detect and prevent through traditional security measures.
The operational impact of this vulnerability extends far beyond simple web application security concerns, as it directly threatens the integrity and confidentiality of enterprise network security infrastructure. An attacker who successfully exploits this vulnerability could gain administrative access to the ProxySG appliance, potentially allowing them to bypass all security policies, monitor all web traffic, or even redirect users to malicious sites. This represents a critical compromise of the security perimeter, as the management console typically contains sensitive configuration data and administrative credentials. The vulnerability is particularly dangerous because it can be exploited through phishing attacks that require minimal technical sophistication from the attacker, yet can result in substantial damage to the organization's security infrastructure. The fact that this vulnerability is separate from CVE-2016-10257 indicates that Symantec had multiple distinct security issues within the same product line that needed addressing.
Organizations affected by this vulnerability should prioritize immediate remediation through the application of available security patches from Symantec, specifically targeting the version releases mentioned in the CVE description. The implementation of additional security controls such as web application firewalls and network segmentation can provide defense-in-depth measures to mitigate potential exploitation attempts. Regular security assessments of management interfaces and input validation testing should be conducted to identify similar vulnerabilities in other network infrastructure components. This vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws, and represents a classic example of how web application security weaknesses can create significant operational risks in enterprise security infrastructure. The ATT&CK framework would categorize this vulnerability under the technique of "Web Application Attack" with potential lateral movement capabilities once the initial compromise is achieved through the management console access.