CVE-2020-15341 in CloudCNM SecuManager
Summary
by MITRE • 09/29/2022
Zyxel CloudCNM SecuManager 3.1.0 and 3.1.1 has an unauthenticated update_all_realm_license API.
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Analysis
by VulDB Data Team • 10/25/2022
The vulnerability identified as CVE-2020-15341 affects Zyxel CloudCNM SecuManager versions 3.1.0 and 3.1.1, representing a critical security flaw in the network management system's API implementation. This issue stems from the absence of proper authentication mechanisms within the update_all_realm_license API endpoint, which allows any remote attacker to execute unauthorized license updates without requiring valid credentials. The affected system operates as a centralized security management platform for Zyxel networking equipment, making this vulnerability particularly dangerous as it could enable attackers to manipulate licensing configurations across managed devices. The vulnerability falls under CWE-287, which addresses improper authentication issues in software systems, specifically targeting the lack of authentication checks for critical administrative functions.
The technical exploitation of this vulnerability occurs through the unauthenticated API endpoint that controls license realm updates, which are essential for managing security features and access controls within the network infrastructure. Attackers can leverage this flaw to modify license configurations, potentially disabling security features, enabling unauthorized access to premium functionalities, or manipulating device access controls. The API endpoint's design fails to implement proper session management, authentication tokens, or user verification mechanisms, creating an attack surface that allows arbitrary code execution or privilege escalation within the security management framework. This vulnerability directly impacts the integrity and availability of the security management system, as unauthorized parties can modify critical licensing parameters that govern device functionality and access permissions.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it compromises the fundamental security posture of networks managed through Zyxel CloudCNM SecuManager. An attacker who successfully exploits this vulnerability could disable security features, modify access control lists, or manipulate device configurations that would otherwise require legitimate administrative credentials. The consequences include potential network infiltration, data exfiltration, and complete compromise of the managed network infrastructure. This vulnerability aligns with ATT&CK technique T1078 which covers valid accounts usage and privilege escalation, as the attacker gains unauthorized access to administrative functions through the lack of authentication controls. The impact is particularly severe in enterprise environments where centralized security management systems control multiple network devices and security policies.
Organizations should implement immediate mitigations including network segmentation to isolate the affected system, disabling unnecessary API endpoints, and implementing network-based access controls to restrict access to the vulnerable API. The most effective long-term solution involves upgrading to patched versions of Zyxel CloudCNM SecuManager that properly implement authentication mechanisms for all administrative APIs. Security administrators should also monitor network traffic for suspicious API access patterns and implement intrusion detection systems that can identify unauthorized access attempts to administrative endpoints. The vulnerability demonstrates the critical importance of principle of least privilege implementation and proper API security design, as the absence of authentication checks for license management functions creates an uncontrolled access point to the entire security management infrastructure. Organizations should also conduct comprehensive security assessments to identify other potentially unauthenticated administrative interfaces within their network management systems.