Cisco SPA100 Series Analog Telephone Adapters Remote Code Execution Vulnerabilities

Vulnerability

Multiple vulnerabilities in Cisco SPA100 Series Analog Telephone Adapters (ATAs) allow an authenticated, adjacent attacker to execute arbitrary code with elevated privileges. The issues are due to improper validation of user-supplied input to the web-based management interface, which is enabled by default. The affected products include all models of the Cisco SPA100 Series, running firmware versions prior to the fixed releases [1].

Exploitation

An attacker must first authenticate to the web-based management interface of an affected device. With authenticated access, the attacker can send specially crafted HTTP requests to the vulnerable interface. The attack requires adjacency to the network (i.e., Layer 2 connectivity) but does not require any user interaction beyond the initial authentication step [1].

Impact

Successful exploitation allows the attacker to execute arbitrary code with elevated privileges on the affected device. This could lead to full compromise of the ATA, including the ability to alter configuration, intercept or redirect voice traffic, and potentially pivot to other network devices [1].

Mitigation

Cisco has released free software updates to address these vulnerabilities. Customers should upgrade to the latest fixed firmware version for their SPA100 Series device as specified in the Cisco Security Advisory. No workarounds that completely mitigate the vulnerabilities are available; however, administrators should ensure that the web-based management interface is not exposed to untrusted networks [1].