CVE-2021-1209 in Small Business
Summary
by MITRE • 01/14/2021
Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV110W, RV130, RV130W, and RV215W Routers could allow an authenticated, remote attacker to execute arbitrary code or cause an affected device to restart unexpectedly. The vulnerabilities are due to improper validation of user-supplied input in the web-based management interface. An attacker could exploit these vulnerabilities by sending crafted HTTP requests to an affected device. A successful exploit could allow the attacker to execute arbitrary code as the root user on the underlying operating system or cause the device to reload, resulting in a denial of service (DoS) condition. To exploit these vulnerabilities, an attacker would need to have valid administrator credentials on the affected device. Cisco has not released software updates that address these vulnerabilities.
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Analysis
by VulDB Data Team • 02/14/2021
The CVE-2021-1209 vulnerability represents a critical security flaw in Cisco Small Business routers including RV110W, RV130, RV130W, and RV215W models. This vulnerability resides within the web-based management interface of these network devices, creating a significant attack surface that could be exploited by authenticated remote adversaries. The flaw stems from inadequate input validation mechanisms that fail to properly sanitize user-supplied data before processing, a weakness that directly aligns with CWE-20, which describes improper input validation as a fundamental security weakness. These routers serve as essential network infrastructure components, often deployed in small business environments where they manage network traffic and provide administrative access points, making them attractive targets for cybercriminals seeking persistent network access.
The technical implementation of this vulnerability involves improper validation of user-supplied input within the web interface's processing pipeline, allowing attackers to inject malicious payloads through crafted HTTP requests. When an authenticated administrator accesses the management interface, the system processes HTTP parameters without adequate sanitization, creating opportunities for command injection or code execution attacks. The vulnerability specifically targets the underlying operating system of these devices, where successful exploitation could result in arbitrary code execution with root privileges, effectively granting attackers complete control over the affected router. This privilege escalation capability, combined with the requirement for only valid administrator credentials, makes the vulnerability particularly dangerous as it requires minimal initial access to achieve maximum impact. The attack vector demonstrates characteristics consistent with ATT&CK technique T1059, specifically command and scripting interpreter, where adversaries leverage legitimate administrative interfaces to execute malicious code.
The operational impact of this vulnerability extends beyond simple privilege escalation to encompass potential denial of service conditions through device reloads, which could disrupt network operations for small business environments. Network administrators relying on these routers for critical infrastructure would face significant risks including unauthorized network access, data exfiltration, and complete network compromise. The vulnerability's exploitation requires only valid administrator credentials, which are often compromised through social engineering, credential stuffing, or other common attack vectors, making it particularly dangerous for organizations with weak credential management practices. The lack of available software updates from Cisco compounds the risk, leaving affected devices permanently vulnerable without mitigation options. Organizations using these routers face potential regulatory compliance issues, as the vulnerability could result in unauthorized access to sensitive network data and disruption of business operations, particularly in environments where network uptime and security are critical requirements.
The mitigation landscape for this vulnerability is severely constrained by Cisco's decision not to release software updates, leaving affected organizations with limited defensive options. Network administrators should implement immediate network segmentation to isolate these devices from critical systems, enforce strong authentication controls including multi-factor authentication, and monitor for unusual administrative access patterns. Organizations should also consider network-based intrusion detection systems that can identify suspicious HTTP request patterns and implement strict access controls limiting administrative access to only necessary personnel. The vulnerability highlights the importance of maintaining current security patches and the risks associated with relying on vendor-provided security updates, particularly in environments where vendors may delay or withhold patches for legacy devices. From a compliance perspective, this vulnerability could violate various regulatory frameworks requiring adequate security controls and incident response procedures, particularly in industries such as healthcare, finance, and government where network security is paramount.