CVE-2020-3490 in Vision Dynamic Signage Director
Summary
by MITRE
A vulnerability in the web-based management interface of Cisco Vision Dynamic Signage Director could allow an authenticated, remote attacker with administrative privileges to conduct directory traversal attacks and obtain read access to sensitive files on an affected system. The vulnerability exists because the web-based management interface does not properly validate user-supplied input. An attacker could exploit this vulnerability by sending a crafted HTTP request that contains directory traversal character sequences to an affected system. A successful exploit could allow the attacker to read files on the underlying operating system with root privileges. To exploit this vulnerability, the attacker would need to have administrative privileges on the affected system.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 11/10/2020
The vulnerability identified as CVE-2020-3490 resides within the web-based management interface of Cisco Vision Dynamic Signage Director, a component designed for managing digital signage content and systems. This particular flaw represents a critical security weakness that could be exploited by malicious actors who have already gained administrative access to the system. The vulnerability stems from insufficient input validation mechanisms within the web interface, specifically failing to properly sanitize user-supplied data before processing. The affected system operates with a web-based management interface that processes HTTP requests containing potentially malicious directory traversal sequences, creating an avenue for unauthorized file access. This type of vulnerability is classified under CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal attacks. The security implications are severe as the vulnerability allows for arbitrary file reading on the underlying operating system, potentially exposing sensitive configuration files, credentials, and system artifacts that could compromise the entire infrastructure.
The technical exploitation of CVE-2020-3490 requires an attacker to have pre-existing administrative privileges on the target system, which significantly reduces the attack surface but does not eliminate the risk entirely. Once authenticated with administrative rights, the attacker can craft specially formatted HTTP requests that include directory traversal sequences such as ../ or ..\ that manipulate the file system navigation paths. These crafted requests bypass the intended access controls and allow the attacker to navigate to restricted directories and read files that should normally be inaccessible. The vulnerability specifically targets the web interface's failure to validate and sanitize input parameters, particularly those related to file path specifications. When the system processes these malformed requests, it fails to properly validate the input, leading to the execution of unintended file system operations. The impact of a successful exploitation extends beyond simple information disclosure, as the attacker could potentially access system configuration files, user credentials, application logs, and other sensitive data that may contain authentication tokens or other critical system information.
The operational impact of this vulnerability within enterprise environments is substantial, particularly in organizations that rely heavily on digital signage management systems for critical communications and operations. Organizations using Cisco Vision Dynamic Signage Director may face significant security risks if this vulnerability is exploited, as it could provide attackers with access to sensitive operational data and system configurations. The vulnerability's requirement for administrative privileges means that it typically affects internal attackers or those who have already compromised administrative accounts through other means, such as credential theft or privilege escalation attacks. From a threat modeling perspective, this vulnerability aligns with ATT&CK technique T1078 which covers valid accounts and privilege escalation, and T1566 which involves credential harvesting through social engineering. The potential for lateral movement within networks increases significantly if attackers can access system files containing network configuration details, user accounts, or service credentials that could be used to access other systems within the same network infrastructure.
Organizations should implement immediate mitigations including applying the vendor-provided security patches and updates released for this vulnerability, as well as implementing network segmentation to limit access to administrative interfaces. Security monitoring should be enhanced to detect unusual patterns in HTTP requests that may indicate directory traversal attempts, and access controls should be strictly enforced to ensure that only authorized personnel have administrative privileges. Regular security assessments and vulnerability scanning should be conducted to identify similar weaknesses in other components of the digital signage infrastructure. The implementation of web application firewalls and input validation controls can provide additional protection layers against similar attacks targeting web interfaces. Additionally, organizations should review their access control policies and ensure that administrative privileges are granted on a need-to-know basis, implementing the principle of least privilege to minimize potential impact from compromised administrative accounts. The vulnerability serves as a reminder of the critical importance of input validation in web applications and the necessity of maintaining up-to-date security patches across all system components.