CVE-2020-3355 in Data Center Network Manager
Summary
by MITRE
A vulnerability in the web-based management interface of Cisco Data Center Network Manager (DCNM) could allow an authenticated, remote attacker with administrative credentials 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. To exploit this vulnerability, the attacker would need administrative credentials on the affected device.
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Analysis
by VulDB Data Team • 10/25/2020
The vulnerability identified as CVE-2020-3355 affects Cisco Data Center Network Manager DCNM, a web-based management interface designed for network administrators to manage data center networks. This system serves as a critical administrative tool for network operations and requires robust security controls to prevent unauthorized access and manipulation. The vulnerability resides within the web interface's input validation mechanisms, specifically targeting the way the system handles user-supplied data in certain fields. The flaw represents a classic cross-site scripting vulnerability that can be exploited by authenticated attackers who possess administrative credentials, making it particularly concerning for enterprise environments where privileged access is tightly controlled but still represents a potential attack vector.
The technical implementation of this vulnerability stems from inadequate input validation within the web-based management interface of Cisco DCNM. When administrators interact with specific data fields through the web interface, the system fails to properly sanitize or validate user input before processing or rendering it back to the browser. This insufficient validation creates an environment where maliciously crafted input can be injected into the application's response, leading to the execution of arbitrary JavaScript code within the victim's browser context. The vulnerability specifically affects fields where user data is accepted and subsequently processed, making it a persistent threat throughout the interface's administrative functions. According to CWE classification, this represents a CWE-79: Cross-site Scripting vulnerability, which is categorized under the broader category of input validation flaws that allow malicious code injection.
The operational impact of this vulnerability extends beyond simple script execution, as it provides attackers with significant privileges within the administrative interface. Successful exploitation could enable attackers to access sensitive browser-based information, manipulate administrative sessions, or even escalate their privileges further within the network management environment. The requirement for administrative credentials to exploit this vulnerability means that the attack vector is somewhat limited compared to unauthenticated exploits, but it remains highly dangerous in environments where privileged accounts are compromised or where attackers have already gained administrative access through other means. This vulnerability directly impacts the integrity and confidentiality of network management operations, potentially allowing attackers to view or modify network configurations, access sensitive operational data, or establish persistent access points within the data center infrastructure. The attack surface is particularly concerning given that DCNM serves as a central management point for large-scale data center networks where administrative credentials are often highly privileged and critical to network operations.
Organizations should implement immediate mitigations including applying Cisco's official security patches and updates to address the input validation deficiencies in the web interface. Network administrators must ensure that all administrative accounts maintain strong authentication controls and that privilege escalation is carefully monitored. The implementation of web application firewalls and additional input sanitization measures can provide additional defense-in-depth layers against exploitation attempts. Security teams should conduct thorough reviews of administrative access logs to identify any suspicious activities that might indicate exploitation attempts. According to ATT&CK framework, this vulnerability maps to T1059.007: Command and Scripting Interpreter: JavaScript, as it enables attackers to execute JavaScript code within the browser context. Organizations should also consider implementing multi-factor authentication for administrative accounts and regular security assessments of web-based management interfaces to prevent similar vulnerabilities from remaining undetected in their network infrastructure. The vulnerability demonstrates the critical importance of input validation in web applications and highlights how seemingly minor implementation flaws can create significant security risks in enterprise network management systems.