External risk intelligence

Neterbit NW-431F Router Authentication Bypass via Predictable Cookie

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2025-67446

The vulnerability affects a network router, a device class designed to act as an internet edge gateway. Authentication bypass in this context allows unauthorized access to administrative functions, which are typically reachable via the management interface on such devices.

Authentication Bypass

Halo Surface Signal: 5 out of 5 — more likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A critical vulnerability has been identified in Neterbit NW-431F routers, allowing unauthorized access to administrative functions by exploiting a predictable authentication mechanism. This could enable attackers to bypass security controls and potentially compromise network devices.

Weak authentication allows unauthorized router access.
Routers are critical network edge devices.
Confirm exposure; administrative access is a high-level risk.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by directly accessing the router's management interface over the network. By manipulating a predictable authentication cookie, they can bypass login controls and gain administrative privileges. This allows them to then access and modify administrative functions on the router.

No privileges required for access.
Modify authentication cookie to bypass login.
Unauthorized access to admin functions.

Live Threat

Current exploitation, exposure, and threat context

An attacker could bypass authentication to access administrative functions on the Neterbit NW-431F Router by exploiting a weak cookie value. This could allow unauthorized modification of router settings when the device is accessible over a network.

Router administrative functions.
Modifying a predictable cookie value.
Unauthorized access and control.

Operational Fix

Recommended remediation, mitigation, and detection steps

Security teams and infrastructure owners are likely responsible for addressing this authentication bypass vulnerability in network routers. The first practical step is to identify all instances of the affected router model, determine their network exposure and business criticality, and then locate the accountable owner to plan remediation.

Network and security teams should own the issue.
Verify router reachability and administrative access.
Plan vendor coordination for mitigation.

Supplementary metadata

CVSS vector

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Frequently asked questions

What is the Neterbit NW-431F Router?

The Neterbit NW-431F is a networking device that acts as a router, managing traffic flow between different network segments. It serves as an edge gateway, which is the hardware entry point that connects an internal home or business network to the broader internet. Because these devices sit between private systems and the public web, they provide core connectivity services that enable devices to communicate online.

What does CVE-2025-67446 mean for my device security?

This vulnerability is an authentication bypass, categorized as CWE-384, which relates to improper session management. In simple terms, the router uses a weak or predictable cookie to verify who is logged in. Because the software generates these values in a way that is easy to guess, an attacker can substitute their own cookie to impersonate a legitimate administrator and gain full control over the device settings.

How does an attacker trigger this authentication bypass?

An attacker triggers this by interacting with the router's web-based management interface over the network. They do not need a valid password or prior access to exploit this; they simply modify the session cookie value in their browser request—for example, changing it to "admin"—to convince the router that they are already authenticated. Normal, non-administrative traffic or attempts to access the device without targeting the cookie mechanism do not trigger the bug.

Do I need to worry if my router is only on an internal network?

Halo Surface Signal indicates that because this device acts as an internet edge gateway, it is frequently reachable from the outside. If your router’s management interface is exposed directly to the internet, your risk is significantly higher. Even if it is strictly on an internal network, any compromised machine on that same local network could reach the management interface and exploit the vulnerability.

What is the first step to address this CVE?

Start by performing an inventory to locate all Neterbit NW-431F routers within your environment. Once identified, evaluate whether the administrative management interface is accessible over the network. Since this issue requires a vendor-provided update, your primary goal is to isolate affected devices from external network access while you coordinate with your infrastructure team to plan and track the necessary vendor mitigation.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.