CVE-2023-20146 in Small Business RV016
Summary
by MITRE • 04/05/2023
Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV016, RV042, RV042G, RV082, RV320, and RV325 Routers could allow an unauthenticated, remote attacker to conduct cross-site scripting (XSS) attacks against a user of the interface. These vulnerabilities are due to insufficient input validation by the web-based management interface. An attacker could exploit these vulnerabilities by sending crafted HTTP requests to an affected device and then persuading a user to visit specific web pages that include malicious payloads. 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. Cisco has not released software updates that address these vulnerabilities.
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Analysis
by VulDB Data Team • 08/25/2025
The vulnerability identified as CVE-2023-20146 represents a critical cross-site scripting flaw affecting multiple Cisco Small Business routers including RV016, RV042, RV042G, RV082, RV320, and RV325 models. This vulnerability resides within the web-based management interface of these network devices, creating a significant security risk for organizations relying on these appliances for their network infrastructure. The flaw stems from inadequate input validation mechanisms that fail to properly sanitize user-supplied data before processing and rendering it within the web interface. This insufficient validation creates an opening for malicious actors to inject and execute arbitrary script code in the context of the vulnerable web application.
The technical exploitation of this vulnerability requires an attacker to craft specially designed HTTP requests that leverage the lack of proper input sanitization. The attack vector is particularly concerning because it does not require authentication, making it accessible to any remote attacker who can reach the affected device's web management interface. The exploitation process involves persuading a legitimate user of the interface to visit web pages containing malicious payloads, which then execute within the user's browser context. This technique aligns with the common exploitation patterns described in the ATT&CK framework under the T1059.007 sub-technique for scripting, where adversaries leverage web-based attack surfaces to execute malicious code. The vulnerability specifically maps to CWE-79 which defines cross-site scripting as a weakness where web applications fail to properly validate or escape user input before incorporating it into dynamic content.
The operational impact of this vulnerability extends beyond simple script execution, as successful exploitation could potentially enable attackers to access sensitive browser-based information and manipulate the web interface functionality. This could lead to unauthorized configuration changes, data exfiltration, or further escalation within the network environment. The fact that Cisco has not released software updates to address these vulnerabilities creates a prolonged exposure window for affected organizations, particularly concerning for small businesses that may not have robust patch management processes. Organizations utilizing these routers for network management face increased risk of lateral movement within their network infrastructure, as compromised management interfaces could provide attackers with elevated privileges to manipulate network configurations and potentially gain access to other connected systems.
Organizations should implement immediate mitigations including network segmentation to isolate affected devices from critical network segments, disabling unnecessary web management access, and implementing web application firewalls to filter malicious requests. Network administrators should also consider restricting access to the web management interfaces through firewall rules and implementing multi-factor authentication where possible. The vulnerability demonstrates the importance of maintaining up-to-date firmware and security patches, as highlighted in industry best practices for network security management. Given the lack of vendor-provided patches, organizations should consider alternative security controls such as intrusion detection systems that can monitor for suspicious HTTP request patterns and potential exploitation attempts against the affected web interfaces. Regular security assessments and vulnerability scanning should be conducted to identify any additional unpatched devices within the network infrastructure that may be similarly affected by similar input validation flaws.