CVE-2014-0737 in Unified IP Phone
Summary
by MITRE
The Cisco Unified IP Phone 7960G 9.2(1) and earlier allows remote attackers to bypass authentication and change trust relationships by injecting a Certificate Trust List (CTL) file, aka Bug ID CSCuj66795.
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Analysis
by VulDB Data Team • 03/30/2019
The vulnerability identified as CVE-2014-0737 affects Cisco Unified IP Phone 7960G devices running firmware version 9.2(1) and earlier, representing a critical security flaw in enterprise communication infrastructure. This issue resides within the device's certificate validation mechanisms and allows unauthorized remote attackers to manipulate trust relationships through malicious certificate injection. The vulnerability specifically targets the Certificate Trust List (CTL) functionality that governs how the phone validates digital certificates for secure communications. The flaw enables attackers to inject unauthorized CTL files that can override legitimate trust relationships, potentially compromising the entire communication ecosystem.
The technical implementation of this vulnerability stems from insufficient input validation and authentication controls within the phone's certificate management system. When the device processes CTL files, it fails to properly verify the authenticity and integrity of these files before incorporating them into its trust store. This weakness creates an attack vector where remote adversaries can upload malicious CTL files that contain forged certificates or modified trust relationships. The vulnerability aligns with CWE-284, which addresses improper access control, and CWE-310, which covers cryptographic issues related to certificate validation. The phone's trust model becomes compromised when legitimate certificate chains are replaced or augmented with malicious entries, allowing attackers to establish unauthorized secure communication channels.
The operational impact of this vulnerability extends beyond simple authentication bypass to encompass complete trust relationship manipulation within the enterprise network. Attackers who successfully exploit this vulnerability can potentially impersonate legitimate network components, intercept encrypted communications, or establish backdoor access points within the VoIP infrastructure. This compromise affects the fundamental security posture of organizations relying on Cisco IP phones for business-critical communications, as the trust relationships that protect voice traffic confidentiality and integrity are undermined. The vulnerability can lead to man-in-the-middle attacks where attackers can decrypt and modify voice communications, potentially leading to data breaches or service disruption. Organizations using these devices may experience cascading security failures as compromised phones can serve as entry points for broader network infiltration.
Mitigation strategies for CVE-2014-0737 require immediate firmware updates to versions that address the certificate validation weaknesses. Cisco released patches specifically targeting this vulnerability in subsequent firmware releases, and organizations must prioritize deployment of these updates across all affected devices. Network segmentation and monitoring should be implemented to detect unauthorized CTL file modifications, as the vulnerability can be exploited without requiring authentication credentials. Security teams should implement certificate monitoring solutions that can detect anomalous trust relationship changes and alert administrators to potential compromise. The mitigation approach aligns with ATT&CK technique T1556.001, which covers credential harvesting through credential access, and T1071.004, which addresses application layer protocol usage for command and control. Organizations should also review their certificate management policies to ensure proper validation and integrity checking of all certificate-related files before deployment. Regular security assessments and vulnerability scanning should be conducted to identify any remaining instances of the vulnerable firmware versions within the network infrastructure.