CVE-2020-3439 in Data Center Network Manager
Summary
by MITRE
A vulnerability in the web-based management interface of Cisco Data Center Network Manager (DCNM) Software could allow an authenticated, remote attacker to conduct a cross-site scripting (XSS) attack against a user of the interface. The vulnerability is due to insufficient input validation by the web-based management interface. An attacker could exploit this vulnerability by inserting malicious data into a specific data field in the interface. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface or access sensitive, browser-based information.
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Analysis
by VulDB Data Team • 11/10/2020
The vulnerability identified as CVE-2020-3439 resides within the web-based management interface of Cisco Data Center Network Manager software, representing a critical security flaw that enables authenticated remote attackers to execute cross-site scripting attacks. This vulnerability specifically targets the insufficient input validation mechanisms implemented within the web interface, creating a pathway for malicious actors to inject harmful script code into the system. The affected interface serves as the primary administrative portal for managing data center network configurations, making it a prime target for attackers seeking unauthorized access to critical network infrastructure. The vulnerability's classification aligns with CWE-79 which specifically addresses cross-site scripting flaws in web applications, where inadequate sanitization of user inputs allows malicious scripts to be executed in the context of other users' browsers. The attack vector requires an authenticated session, meaning that an attacker must first establish valid credentials to exploit this weakness, but once authenticated, the potential for damage increases significantly.
The technical exploitation of this vulnerability occurs through the manipulation of specific data fields within the web interface, where the application fails to properly validate or sanitize user-provided input before processing or displaying it. When an attacker successfully injects malicious script code into these vulnerable fields, the system processes the input without adequate protection mechanisms, allowing the malicious code to execute in the victim's browser context. This execution environment provides attackers with the ability to access sensitive browser-based information, potentially including session cookies, user credentials, or other confidential data stored within the browser. The impact extends beyond simple script execution, as the attacker can leverage this capability to perform actions on behalf of the authenticated user, potentially leading to complete system compromise or unauthorized access to network resources. The vulnerability demonstrates a fundamental flaw in the input handling architecture of the DCNM interface, where the system fails to implement proper sanitization and validation controls for user-supplied data.
The operational impact of CVE-2020-3439 within data center environments is particularly severe due to the critical nature of network management interfaces and the privileged access they provide. Organizations utilizing Cisco DCNM software face significant risk of unauthorized access to their data center networks, potentially enabling attackers to manipulate network configurations, access sensitive operational data, or establish persistent access points within their infrastructure. The authenticated nature of the attack means that attackers who have gained legitimate access to the system through other means can leverage this vulnerability to escalate their privileges or maintain long-term access. This vulnerability directly impacts the CIA triad by compromising both confidentiality and integrity of the network management system, potentially allowing attackers to view sensitive configuration data or modify network settings without detection. The attack can be executed remotely, eliminating the need for physical access to the network infrastructure and making it particularly dangerous in environments where network management interfaces are exposed to external networks or accessed through remote management protocols.
Mitigation strategies for CVE-2020-3439 should focus on implementing comprehensive input validation and output encoding controls within the web interface. Organizations should immediately apply the vendor-provided security patches and updates to address the vulnerability, while also implementing additional security measures such as web application firewalls to monitor and filter malicious input attempts. Network segmentation and access controls should be strengthened to limit the scope of potential exploitation, ensuring that only authorized personnel have access to the management interface. Regular security assessments and penetration testing should be conducted to identify similar vulnerabilities within the network management infrastructure, while also implementing monitoring solutions to detect suspicious activities within the web interface. The implementation of Content Security Policy headers and proper input sanitization mechanisms can provide additional protection layers against XSS attacks, ensuring that even if an attacker manages to inject malicious code, the execution will be prevented or limited. Security awareness training for administrators should also be reinforced to prevent social engineering attacks that might lead to credential compromise, as the vulnerability requires authenticated access to be exploited effectively.