CVE-2015-7276 in C2000T
Summary
by MITRE
Technicolor C2000T and C2100T uses hard-coded cryptographic keys.
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Analysis
by VulDB Data Team • 02/05/2024
The vulnerability identified as CVE-2015-7276 affects Technicolor C2000T and C2100T wireless routers, representing a critical weakness in embedded device security architecture. These telecommunications devices utilize hard-coded cryptographic keys within their firmware, creating a fundamental flaw that undermines the security of the entire network infrastructure they manage. The presence of such static cryptographic material violates established security principles and creates an exploitable condition that affects millions of devices deployed globally in residential and small business environments.
This technical flaw constitutes a direct violation of security best practices and aligns with CWE-327, which addresses the use of weak cryptographic algorithms and hardcoded keys. The hard-coded keys provide attackers with persistent access to the device's cryptographic functions, enabling them to decrypt communications, forge authentication tokens, and potentially gain administrative control over the router. The vulnerability exists at the firmware level where cryptographic material is embedded directly into the code rather than being dynamically generated or securely stored, making it accessible through reverse engineering or simple firmware extraction techniques. This weakness creates a persistent backdoor that remains effective across device reboots and firmware updates that fail to replace the compromised keys.
The operational impact of this vulnerability extends beyond individual device compromise to threaten entire network infrastructures and user privacy. Attackers can exploit the hardcoded keys to intercept and manipulate network traffic, potentially accessing sensitive information transmitted through the router. The vulnerability affects both wired and wireless communications passing through these devices, creating a comprehensive attack surface that can be leveraged for man-in-the-middle attacks, session hijacking, and data exfiltration. Network administrators face the challenge of managing security risks without the ability to easily update or replace compromised cryptographic material, as the keys are embedded within the device firmware itself. The vulnerability also creates opportunities for attackers to establish persistent access points within networks, potentially enabling long-term surveillance or lateral movement attacks against connected systems.
Mitigation strategies for CVE-2015-7276 require immediate attention from device owners and network administrators, though the nature of hardcoded keys presents significant challenges for remediation. The most effective immediate action involves changing default administrative credentials and implementing network segmentation to limit the attack surface. However, the fundamental flaw cannot be fully resolved through configuration changes alone, as the cryptographic keys themselves remain embedded within the device firmware. Device manufacturers should be contacted to determine if firmware updates are available, though such updates may not be possible if the keys are permanently hardcoded. Network monitoring solutions should be deployed to detect anomalous traffic patterns that might indicate exploitation attempts. The vulnerability also highlights the importance of implementing secure boot processes and key management practices, aligning with ATT&CK technique T1552.001 for credential access and T1046 for network service scanning. Organizations should consider replacing affected devices with models that implement proper cryptographic key management and avoid the use of hardcoded credentials or keys in embedded systems, following security frameworks that emphasize the principle of least privilege and secure configuration management.