CVE-2015-0670 in IP Phone
Summary
by MITRE
The default configuration of Cisco Small Business IP phones SPA 300 7.5.5 and SPA 500 7.5.5 does not properly support authentication, which allows remote attackers to read audio-stream data or originate telephone calls via a crafted XML request, aka Bug ID CSCuo52482.
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Analysis
by VulDB Data Team • 04/16/2022
The vulnerability identified as CVE-2015-0670 affects Cisco Small Business IP phones SPA 300 and SPA 500 series operating on firmware versions 7.5.5 and earlier. This issue stems from inadequate authentication mechanisms within the default configuration of these telephony devices, creating a significant security gap that enables unauthorized remote access to critical communication functions. The flaw specifically impacts the XML-based provisioning and management interfaces that these devices utilize for configuration and operation. The vulnerability is particularly concerning because it allows attackers to exploit the weak authentication controls to gain access to audio streams and initiate telephone calls without proper authorization, effectively compromising the confidentiality and integrity of voice communications within the affected networks.
The technical implementation of this vulnerability resides in the insufficient authentication validation processes within the web-based management interface of the affected Cisco IP phones. When these devices receive crafted XML requests through their HTTP interfaces, the authentication mechanisms fail to properly verify the legitimacy of the requesting entity. This authentication bypass occurs because the default configuration does not enforce proper access controls or require valid credentials before processing administrative commands. The flaw enables attackers to send specially crafted XML payloads that can trigger the phone to transmit audio data or place calls without requiring any authentication credentials, effectively rendering the device's security controls ineffective. This represents a fundamental failure in the device's security architecture where the principle of least privilege is not properly enforced, allowing any remote attacker to manipulate the device's functionality.
The operational impact of CVE-2015-0670 extends beyond simple unauthorized access to encompass potential surveillance and communication disruption capabilities. Attackers can leverage this vulnerability to eavesdrop on audio conversations, which directly violates privacy and confidentiality requirements for business communications. Additionally, the ability to originate telephone calls without authorization creates opportunities for fraudulent activities, toll fraud, and disruption of legitimate business communications. The remote nature of the attack means that threat actors do not require physical access to the devices or network proximity to exploit the vulnerability, making it particularly dangerous in enterprise environments where these devices may be exposed to external network traffic. This vulnerability essentially transforms the affected IP phones from secure communication devices into potential entry points for broader network compromise, as attackers can use the device as a pivot point for further reconnaissance and lateral movement within the network infrastructure.
Organizations affected by this vulnerability should implement immediate mitigations to address the authentication weaknesses in their Cisco Small Business IP phone deployments. The primary recommendation involves updating the firmware to versions that contain proper authentication controls and security patches released by Cisco to address this specific vulnerability. Network segmentation and access control measures should be implemented to limit direct network access to these devices, particularly restricting access to their HTTP management interfaces from untrusted networks. Additionally, organizations should consider disabling unnecessary services and features on the affected devices, including the web management interface, when they are not actively required for administration. This vulnerability aligns with CWE-287, which addresses improper authentication issues, and represents a clear violation of the ATT&CK technique T1071.004 for application layer protocol: DNS, as the attack vectors leverage the devices' network protocols for unauthorized access. Security monitoring should be enhanced to detect unusual call patterns or unauthorized access attempts to these devices, as such activities may indicate exploitation of this vulnerability.