CVE-2021-1316 in RV016
Summary
by MITRE • 02/05/2021
Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV016, RV042, RV042G, RV082, RV320, and RV325 Routers could allow an authenticated, remote attacker to inject arbitrary commands that are executed with root privileges. These 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 a targeted device. A successful exploit could allow the attacker to execute arbitrary code as the root user on the underlying operating system. To exploit these vulnerabilities, an attacker would need to have valid administrator credentials on an affected device.
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Analysis
by VulDB Data Team • 02/24/2021
The CVE-2021-1316 vulnerability affects Cisco Small Business routers including RV016, RV042, RV042G, RV082, RV320, and RV325 models, representing a critical command injection flaw in their web-based management interfaces. This vulnerability stems from insufficient input validation mechanisms that fail to properly sanitize user-supplied data before processing within the router's operating system. The flaw exists in the authentication layer where legitimate administrative credentials are required but insufficiently validated when processing HTTP requests containing malicious payloads. The vulnerability is classified under CWE-77 as "Improper Neutralization of Special Elements used in a Command ('Command Injection')", which directly aligns with the attack patterns observed in this exploit. The affected devices operate on embedded operating systems where web interfaces communicate directly with underlying shell commands, creating a direct pathway for arbitrary code execution when user input is not properly escaped or filtered.
The operational impact of this vulnerability is severe as it enables authenticated remote code execution with root privileges, effectively granting attackers complete control over the affected router systems. An attacker with valid administrator credentials can craft malicious HTTP requests that bypass normal input validation checks and execute arbitrary commands directly on the router's operating system. This creates a persistent backdoor capability that allows for network reconnaissance, traffic interception, and potential lateral movement within the network. The vulnerability's exploitation requires minimal prerequisites beyond legitimate administrative access, making it particularly dangerous in environments where administrative credentials might be compromised through social engineering, credential theft, or weak password practices. The attack vector follows standard command injection patterns documented in the MITRE ATT&CK framework under technique T1059.001 for Command and Scripting Interpreter, specifically focusing on the execution of system commands through web interfaces.
Mitigation strategies for CVE-2021-1316 should prioritize immediate patching of affected devices through Cisco's security advisories, as the vendor has released firmware updates addressing the input validation flaws. Network segmentation and access control measures must be implemented to limit administrative access to these devices, ensuring that only authorized personnel can reach the management interfaces. The principle of least privilege should be enforced by creating separate administrative accounts with limited permissions and implementing multi-factor authentication where possible. Network monitoring should be enhanced to detect unusual HTTP request patterns that might indicate exploitation attempts, particularly focusing on requests containing command injection payloads. Organizations should conduct thorough vulnerability assessments to identify all affected devices and implement network access controls to prevent unauthorized access to router management interfaces. Additionally, regular security audits of administrative credentials and access logs should be performed to detect potential compromise of administrative accounts. The vulnerability highlights the importance of input sanitization and output encoding practices in web applications, reinforcing industry standards such as OWASP Top Ten's A03:2021 Injection and A05:2021 Security Misconfiguration requirements for proper validation of user inputs.