Cisco Small Business RV110W, RV130, RV130W, and RV215W Routers Management Interface Remote Command Execution and Denial of Service Vulnerabilities

Vulnerability

The web-based management interface of Cisco Small Business RV110W, RV130, RV130W, and RV215W Routers contains multiple buffer overflow vulnerabilities [1]. These vulnerabilities stem from improper validation of user-supplied input in the web-based management interface. Affected products include RV110W Wireless-N VPN Firewall, RV130 VPN Router, RV130W Wireless-N Multifunction VPN Router, and RV215W Wireless-N VPN Router. The interface is accessible via local LAN connection (cannot be disabled) or through WAN if remote management is enabled (disabled by default) [1]. Cisco has not released software updates addressing these vulnerabilities [1].

Exploitation

An attacker must have valid administrator credentials for the affected device [1]. With authenticated access, the attacker sends crafted HTTP requests to the web-based management interface. The vulnerability can be triggered over a local LAN connection or over the WAN if remote management is enabled. No user interaction beyond the attacker's own actions is required. The exact sequence involves crafting HTTP requests that cause a buffer overflow in the device's input handling [1].

Impact

Successful exploitation allows the attacker to execute arbitrary code as the root user on the underlying operating system, leading to full compromise of the device. Alternatively, the attacker can cause the device to reload, resulting in a denial of service (DoS) condition. The impact is complete loss of confidentiality, integrity, and availability of the affected router [1].

Mitigation

As of the publication date (January 13, 2021), Cisco has not released software updates to address these vulnerabilities. No workarounds are available [1]. Organizations should consider disabling remote management if enabled, restrict access to the web-based management interface to trusted administrative networks, and monitor Cisco advisory cisco-sa-rv-overflow-WUnUgv4U for future updates. These products may be end-of-life; contact Cisco for support options [1].