Cisco Small Business RV Series Routers Management Interface Command Injection Vulnerabilities

Vulnerability

The web-based management interface of Cisco Small Business RV016, RV042, RV042G, RV082, RV320, and RV325 routers contains multiple command injection vulnerabilities (CVE-2021-1317). These flaws arise due to improper validation of user-supplied input. An attacker with valid administrator credentials can inject arbitrary commands that are executed with root privileges. All firmware versions prior to the fixed releases are affected.

Exploitation

To exploit these vulnerabilities, an attacker must have valid administrator credentials for an affected device. The attacker sends specially crafted HTTP requests to the web-based management interface. The improper input validation allows the injection of operating system commands, which are then executed on the underlying system with root privileges. No additional user interaction is required beyond the authenticated session.

Impact

A successful exploit allows the attacker to execute arbitrary commands as the root user on the underlying operating system. This provides full control over the router, including the ability to modify configuration, exfiltrate data, or pivot to internal networks. The consequences include complete compromise of confidentiality, integrity, and availability of the device and potentially the network it manages.

Mitigation

Cisco has released free software updates to address these vulnerabilities, as detailed in the security advisory [1]. Users are advised to upgrade to the fixed firmware versions for their specific router model. Cisco does not mention workarounds; therefore, upgrading is the recommended mitigation. No known KEV listing at the time of publication.