CVE-2026-76945 in NE2-D11
Summary
by MITRE • 08/28/2026
The affected Ebyte device relies on client-managed authentication tokens without sufficient server-side validation. An attacker may replay or manipulate authentication tokens to gain unauthorized access to administrative functionality.
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Analysis
by VulDB Data Team • 08/28/2026
The vulnerability described involves a critical flaw in the authentication mechanism of an Ebyte IoT device, specifically centering on the improper handling and validation of client-managed authentication tokens. In secure system architectures, it is standard practice for servers to maintain authoritative state regarding session validity, token expiration, and user permissions. However, this implementation delegates too much trust to the client side, allowing the application or interface interacting with the device to manage these credentials without rigorous server-side verification. This architectural decision creates a significant security gap where the integrity of the authentication process is compromised because the server fails to independently validate the authenticity, freshness, and scope of the tokens presented by the client.
From a technical perspective, this flaw manifests as an inability to detect replay attacks or token manipulation attempts. Since the server does not sufficiently check whether a token has already been used, expired, or altered in transit, an attacker can intercept valid authentication credentials through network sniffing or other means and reuse them at a later time. Furthermore, because there is insufficient validation of the token's structure or associated metadata, an adversary may modify existing tokens to escalate privileges or bypass access controls entirely. This lack of server-side enforcement effectively neutralizes the protective measures intended by the use of authentication tokens, rendering them susceptible to exploitation by any actor with network-level visibility or limited local access.
The operational impact of this vulnerability is severe, as it directly enables unauthorized access to administrative functionality within the device's management interface. Administrative controls typically grant full control over device configuration, firmware updates, and network settings. If an attacker successfully replays a valid token or manipulates one to gain admin rights, they can alter critical system parameters, potentially leading to service disruption, data exfiltration, or the installation of malicious code. In the context of IoT devices, which often serve as gateways for broader networks, compromising administrative access can provide a foothold for lateral movement into connected systems, thereby expanding the blast radius of the initial breach beyond just the single device.
This vulnerability aligns with CWE-287, Improper Authentication, specifically relating to insufficient verification of credentials or tokens by the server side. It also maps closely to MITRE ATT&CK technique T1078, Valid Accounts, where attackers leverage legitimate credentials that have been stolen or manipulated to gain persistent access. The specific behavior of reusing intercepted credentials corresponds to aspects of credential replay attacks often seen in web application and API security contexts. To mitigate this risk, developers must implement strict server-side validation for all authentication tokens, including checks for expiration times, unique identifiers such as nonces to prevent replays, and digital signatures to ensure integrity. Additionally, adopting stateful session management or implementing short-lived token lifecycles with refresh mechanisms can significantly reduce the window of opportunity for attackers to exploit these weaknesses.