Cisco Small Business Routers RV016, RV042, RV042G, RV082, RV320, and RV325 Command Injection Vulnerability

Vulnerability

The vulnerability, identified as CVE-2019-15957, is a command injection flaw in the web-based management interface of Cisco Small Business RV Series routers, including models RV016, RV042, RV042G, RV082, RV320, and RV325. The issue stems from insufficient validation of user-supplied input in a specific field of the interface. An authenticated attacker with administrative privileges can inject arbitrary commands that are then executed on the underlying Linux operating system with root privileges. All firmware versions prior to the fixed releases are affected [1].

Exploitation

To exploit this vulnerability, an attacker must have valid administrative credentials and be able to reach the web-based management interface (typically over the network). The attacker then provides specially crafted input to a vulnerable field in the interface. The malicious input, when processed by the device, results in the execution of arbitrary commands as root. No additional user interaction or complex prerequisites are required beyond administrative access and network connectivity [1].

Impact

Successful exploitation allows the attacker to execute arbitrary commands on the affected device's operating system with root privileges. This gives the attacker full control over the device, enabling actions such as modifying configuration, accessing sensitive data, disabling security controls, or using the device as a pivot point for further attacks on the internal network. The impact is a complete compromise of confidentiality, integrity, and availability of the device and potentially the network it serves [1].

Mitigation

Cisco has released free software updates to address this vulnerability. The fixed releases are available for download from Cisco's official support site. There are no workarounds to mitigate the vulnerability without upgrading the firmware. Users should upgrade to the latest firmware version for their specific router model as indicated in Cisco's security advisory [1]. This vulnerability is not currently listed in the Known Exploited Vulnerabilities (KEV) catalog as of the publication date.