CVE-2026-89207 in WTV676-HB6035 Web Interface
Summary
by MITRE • 09/16/2026
A vulnerability has been identified in WTV676-HB6035 Web Interface (All versions < V3.94), WTV776-HB6035 Web Interface (All versions < V4.17). Affected devices do not properly validate input received from backend services. This could allow an unauthenticated remote attacker to force the device into protection mode, which results in losing remote connectivity functions (Web Access).
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Analysis
by VulDB Data Team • 09/16/2026
The identified vulnerability affects specific models of network infrastructure equipment, namely the WTV676-HB6035 and WTV776-HB6035 web interfaces running versions prior to V3.94 and V4.17 respectively. This security flaw stems from a fundamental failure in input validation mechanisms when processing data received from backend services. In secure software architecture, any data originating from external or internal sources must be rigorously sanitized and validated before being processed by the application logic. The absence of these checks allows malicious actors to inject malformed or unexpected payloads that manipulate the device's operational state without requiring authentication credentials. This lack of validation represents a critical breakdown in the principle of least privilege and secure coding practices, exposing the management plane to unauthorized manipulation.
From an offensive security perspective, this vulnerability aligns with CWE-20 Improper Input Validation, as the system fails to verify that incoming data conforms to expected formats or constraints before execution. Furthermore, because it enables an unauthenticated attacker to alter device configuration and behavior, it is closely related to CWE-74 Injection in contexts where backend service responses are treated as trusted input without verification. The attack vector allows a remote adversary operating from any network location with connectivity to the management interface to exploit this weakness. By crafting specific requests that trigger erroneous processing within the backend services, an attacker can force the device into a protective state designed for fault tolerance or security lockdowns.
The operational impact of exploiting this vulnerability is severe and directly impacts business continuity. When triggered, the device enters protection mode, which effectively disables remote connectivity functions including web access. This results in a denial of service condition for administrators who rely on these interfaces for monitoring, configuration management, and troubleshooting. Unlike traditional denial-of-service attacks that consume bandwidth or resources, this vulnerability achieves availability disruption by logically locking out legitimate users through misconfiguration induced by the attacker. The inability to remotely manage the device may necessitate physical access to reset configurations, significantly increasing operational costs and downtime during incident response efforts.
This type of attack is consistent with techniques observed in the MITRE ATT&CK framework under T1529 System Shutdown or Reboot if it involves a hard reset, but more accurately falls under configuration manipulation that leads to service unavailability. It highlights the risk associated with trusting internal services implicitly without implementing defense-in-depth strategies such as input sanitization at multiple layers of the application stack. The vulnerability underscores the importance of validating not only user-supplied data from web forms but also responses and data structures returned by backend microservices or API endpoints that interact directly with critical system controls.
To mitigate this risk, organizations must prioritize immediate patching to upgrade affected devices to version V3.94 for WTV676-HB6035 models or V4.17 for WTV776-HB6035 models where available. If upgrading is not immediately feasible, network segmentation should be implemented to restrict access to the management interfaces exclusively from trusted administrative subnets using firewall rules and VLAN isolation. Additionally, implementing strict input validation logic on both client-side and server-side applications can prevent malformed data from reaching critical processing functions. Security teams should also monitor for anomalous traffic patterns targeting these specific device models that resemble injection attempts or unusual configuration changes indicative of exploitation activity. Regular vulnerability assessments focusing on web interface security and backend service integration points are essential to identify similar weaknesses across the infrastructure portfolio before they can be leveraged by adversaries.