CVE-2018-16218 in Ultra-elegant IP Phone SIP-T41P
Summary
by MITRE
A CSRF (Cross Site Request Forgery) in the web interface of the Yeahlink Ultra-elegant IP Phone SIP-T41P firmware version 66.83.0.35 allows a remote attacker to trigger code execution or settings modification on the device by providing a crafted link to the victim.
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Analysis
by VulDB Data Team • 09/24/2023
The vulnerability identified as CVE-2018-16218 represents a critical cross site request forgery flaw within the web interface of the Yeahlink Ultra-elegant IP Phone SIP-T41P firmware version 66.83.0.35. This vulnerability operates at the application layer and specifically targets the authentication and authorization mechanisms of the device's web management interface. The flaw allows remote attackers to manipulate the device's configuration and potentially execute arbitrary code by tricking authenticated users into clicking maliciously crafted links. The vulnerability stems from the absence of proper anti-csrf tokens or validation mechanisms in the web interface, making it susceptible to unauthorized operations. According to CWE-352, this represents a classic cross site request forgery vulnerability where the application fails to validate that requests originate from legitimate sources. The attack vector is particularly dangerous because it leverages the trust relationship between the device and its authenticated users, allowing attackers to perform actions that should only be executable by authorized personnel.
The technical implementation of this vulnerability exploits the lack of request origin verification within the web interface of the SIP-T41P device. When a user accesses the device's web management interface, the system should validate that all requests are legitimate and originate from the same user session. However, the firmware fails to implement proper anti-csrf protection mechanisms, allowing attackers to construct malicious requests that appear to come from authenticated users. The vulnerability specifically affects the device's configuration management functions, enabling attackers to modify critical settings such as SIP server configurations, network parameters, or administrative credentials. The attack requires minimal user interaction, typically involving the victim clicking on a malicious link that automatically submits requests to the device's web interface. This type of vulnerability falls under the ATT&CK technique T1078.004 which describes Valid Accounts usage for privilege escalation and persistence. The absence of proper session validation creates an exploitable condition where attackers can manipulate the device's operational parameters without direct physical access or authentication credentials.
The operational impact of CVE-2018-16218 extends beyond simple configuration modification to potentially compromise the entire communication infrastructure managed by the affected device. An attacker who successfully exploits this vulnerability could redirect SIP traffic to malicious servers, intercept voice communications, or completely disable the device's functionality. The remote code execution capability, while not explicitly confirmed in the description, represents a significant concern as it could allow attackers to install backdoors, modify firmware, or establish persistent access to the network. The vulnerability affects organizations that rely on VoIP infrastructure, potentially creating entry points for broader network infiltration attacks. The attack scenario typically involves social engineering campaigns where attackers send phishing emails containing malicious links designed to exploit the CSRF vulnerability. This creates a dangerous situation for enterprises where the device serves as a communication gateway, potentially allowing attackers to disrupt business communications or gain access to sensitive voice data.
Mitigation strategies for this vulnerability should focus on implementing robust anti-csrf protection mechanisms within the web interface. Organizations should immediately upgrade to firmware versions that include proper anti-csrf token validation and session management controls. Network segmentation should be implemented to isolate VoIP devices from critical network segments, reducing the potential impact of exploitation. The implementation of web application firewalls and intrusion detection systems can help identify and block malicious requests targeting the vulnerable interface. Additionally, administrators should disable unnecessary web management interfaces and restrict access to these interfaces through network access control lists. According to NIST SP 800-53 security controls, organizations should implement proper access control mechanisms and authentication protocols to prevent unauthorized modifications. Regular security audits and vulnerability assessments should be conducted to identify similar issues in other networked devices. The vulnerability also highlights the importance of secure coding practices and the implementation of proper input validation and session management within embedded web interfaces. Organizations should also consider implementing network monitoring solutions that can detect anomalous behavior patterns indicative of exploitation attempts, particularly around the device's web management ports. The remediation process should include comprehensive testing to ensure that the firmware updates do not introduce compatibility issues with existing network configurations while effectively addressing the CSRF vulnerability.