CVE-2020-15340 in CloudCNM SecuManager
Summary
by MITRE • 09/29/2022
Zyxel CloudCNM SecuManager 3.1.0 and 3.1.1 has a hardcoded opt/axess/AXAssets/default_axess/axess/TR69/Handlers/turbolink/sshkeys/id_rsa SSH key.
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Analysis
by VulDB Data Team • 09/29/2022
The vulnerability identified as CVE-2020-15340 affects Zyxel CloudCNM SecuManager versions 3.1.0 and 3.1.1, representing a critical security flaw that exposes hardcoded cryptographic materials within the system's configuration. This issue falls under the category of hardcoded credentials and cryptographic keys, which is classified as CWE-259 and CWE-320 within the Common Weakness Enumeration framework. The vulnerability manifests through a hardcoded SSH private key located at the specific path opt/axess/AXAssets/default_axess/axess/TR69/Handlers/turbolink/sshkeys/id_rsa, which represents a fundamental breach in the principle of least privilege and secure configuration management.
The technical implementation of this vulnerability involves the inclusion of a private SSH key directly within the software distribution, making it accessible to any individual who can obtain access to the system or its configuration files. This hardcoded key serves as a backdoor mechanism that allows unauthorized parties to establish secure shell connections to systems managed by the SecuManager platform. The presence of such a key violates fundamental security principles including the separation of concerns and the proper handling of cryptographic materials, as outlined in NIST SP 800-57 and other cryptographic standards. The attack surface is significantly expanded since the key remains static and cannot be rotated or updated without a software patch, creating a persistent threat vector that remains active throughout the system's operational lifecycle.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it enables attackers to escalate privileges and potentially gain control over the entire network infrastructure managed by the SecuManager system. This vulnerability can be leveraged for lateral movement within the network, allowing attackers to pivot from the compromised system to other network segments that may contain sensitive data or critical systems. The attack pattern aligns with techniques described in the MITRE ATT&CK framework under T1078 (Valid Accounts) and T1566 (Phishing for Information) as attackers can use the hardcoded credentials to establish persistent access and then conduct reconnaissance activities. The vulnerability also represents a significant risk to compliance requirements such as those outlined in PCI DSS, HIPAA, and SOX, which mandate the proper handling of cryptographic keys and the implementation of secure configuration management practices.
Organizations affected by this vulnerability should implement immediate mitigations including the removal of the hardcoded key from all affected systems, the implementation of proper key rotation procedures, and the deployment of network monitoring to detect unauthorized access attempts. The recommended remediation strategy involves updating to the patched version of the SecuManager software, which should address the hardcoded key issue through proper key management and secure configuration practices. Additionally, organizations should conduct comprehensive security assessments to identify any other hardcoded credentials or cryptographic materials within their systems, as this vulnerability represents a broader class of issues that can compromise system integrity. The implementation of automated key management systems and regular security audits can help prevent similar issues from occurring in the future, aligning with best practices recommended by the Center for Internet Security and other cybersecurity frameworks that emphasize the importance of proper credential and key management throughout the system lifecycle.