CVE-2021-1217 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.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 02/14/2021
The vulnerability identified as CVE-2021-1217 affects Cisco Small Business routers including models RV110W, RV130, RV130W, and RV215W, representing a critical security flaw in the web-based management interface design. This issue stems from inadequate input validation mechanisms that fail to properly sanitize user-supplied data before processing within the router's operating system. The flaw exists in the web interface's handling of HTTP requests, creating a pathway for authenticated remote code execution and denial of service conditions. The vulnerability is particularly concerning because it allows attackers with valid administrative credentials to escalate privileges and execute arbitrary commands with root-level access, effectively compromising the entire device and potentially the network it protects.
The technical exploitation of CVE-2021-1217 relies on sending specially crafted HTTP requests to the affected router's web management interface, bypassing normal input validation checks. This type of vulnerability maps directly to CWE-20, which describes improper input validation, and falls under the ATT&CK technique T1059.007 for Command and Scripting Interpreter. The improper validation allows attackers to inject malicious payloads that are then executed within the router's operating system environment, where they run with the highest privileges available. The vulnerability could result in complete system compromise, enabling attackers to install backdoors, modify network configurations, or establish persistent access points within the network infrastructure. The fact that these routers are designed for small business environments makes them particularly attractive targets, as they often lack the sophisticated security monitoring and patch management processes found in enterprise environments.
The operational impact of CVE-2021-1217 extends beyond simple privilege escalation to encompass potential network disruption and data exfiltration capabilities. When exploited, the vulnerability can cause unexpected device reboots, leading to denial of service conditions that can disrupt business operations for small organizations. The ability to execute arbitrary code as root user provides attackers with complete control over the router's functionality, including the potential to modify firewall rules, redirect traffic, or disable security features. This vulnerability represents a significant risk to organizations relying on these devices for network security, as compromised routers can serve as entry points for broader network attacks. The lack of available software updates from Cisco for these specific models compounds the risk, leaving affected organizations with no official remediation path.
Organizations affected by CVE-2021-1217 should implement immediate network segmentation strategies to limit the potential impact of exploitation. Network administrators should consider disabling the web-based management interface entirely and relying on secure SSH or Telnet connections for router management. Access control measures should be strengthened through multi-factor authentication and regular credential rotation. Monitoring network traffic for suspicious HTTP requests and unusual device behavior can help detect exploitation attempts. The vulnerability also highlights the importance of maintaining updated firmware and security patches, particularly for network infrastructure devices that may not receive regular updates from vendors. Organizations should consider alternative router models that provide better security track records and vendor support for security vulnerabilities. Additionally, implementing network intrusion detection systems and regular security assessments can help identify and mitigate potential exploitation attempts before they cause significant damage to network operations.