CVE-2026-77966 in NA111-M
Summary
by MITRE • 08/31/2026
The affected Ebyte
product does not provide separation between limited and administrative management functions. A low privileged authenticated attacker could access security sensitive configuration functions and modify settings that affect the confidentiality, integrity, or availability of the device.
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Analysis
by VulDB Data Team • 08/31/2026
The vulnerability described represents a critical failure in role-based access control mechanisms within Ebyte network products, specifically manifesting as an improper separation between limited user privileges and administrative management functions. In secure system design, it is imperative that distinct roles are enforced with strict boundaries to prevent lower-privileged entities from executing high-level operations. This specific flaw indicates that the authentication subsystem fails to validate whether a logged-in user possesses the requisite authority level before processing configuration requests. Consequently, an attacker who has obtained valid credentials for a standard or limited account can bypass intended security restrictions and interact directly with administrative interfaces or API endpoints designed exclusively for system administrators.
From a technical perspective, this issue aligns closely with CWE-269, which classifies Improper Privilege Control, and more specifically CWE-862, the Missing Authorization vulnerability. The core defect lies in the application logic rather than a cryptographic weakness or input parsing error; the server accepts requests from authenticated users without verifying their role against the required permissions for the targeted action. This allows for unauthorized modification of critical system settings that govern network behavior, security policies, and operational parameters. Because the attacker is already authenticated, traditional perimeter defenses such as firewalls may not detect this activity as malicious, making it particularly insidious compared to unauthenticated attacks.
The operational impact of this vulnerability is severe due to its direct effect on the confidentiality, integrity, and availability triad of information security. An adversary with low-privileged access can alter configuration settings that might disable logging mechanisms, thereby obscuring their presence and hindering forensic analysis. They may also modify network routing rules or firewall policies to facilitate lateral movement within a protected environment or redirect traffic through compromised nodes for interception. Furthermore, the ability to change availability-related configurations allows an attacker to degrade service quality or cause complete denial of service by misconfiguring critical system parameters, effectively turning legitimate administrative tools into weapons against their own infrastructure.
This scenario is consistent with tactics observed in advanced persistent threat campaigns and aligns with MITRE ATT&CK techniques such as T1078 Valid Accounts, where attackers leverage existing credentials to gain access, followed by T1546 Event Triggered Execution or various configuration modification techniques that allow for persistence or privilege escalation. The lack of separation between management functions means that a single compromised low-level account can serve as a pivot point for significant system compromise, bypassing the principle of least privilege which is foundational to secure architecture.
To mitigate this vulnerability, immediate remediation should focus on implementing robust role-based access control (RBAC) at both the application and API layers. Developers must ensure that every administrative endpoint or configuration function explicitly checks the user's role before processing any request, rejecting actions from non-administrative accounts with appropriate HTTP error codes such as 403 Forbidden. Additionally, adopting a defense-in-depth strategy is crucial; this includes implementing strict input validation on all configuration parameters to prevent logic-based exploits even if access controls are bypassed, and ensuring that sensitive administrative functions require multi-factor authentication or additional verification steps beyond simple password entry. Regular security audits and penetration testing focused on privilege escalation paths should be conducted to identify similar gaps in other modules of the product suite before deployment in production environments.