CVE-2026-0407: NETGEAR WiFi Extender Auth Bypass Flaw

CVE-2026-0407 Overview

An insufficient authentication vulnerability exists in NETGEAR WiFi range extenders that allows a network adjacent attacker with WiFi authentication or a physical Ethernet port connection to bypass the authentication process and access the admin panel. This vulnerability, classified under CWE-287 (Improper Authentication), enables attackers on the local network to gain unauthorized administrative access to affected devices without proper credential verification.

Critical Impact
Attackers with network adjacency can bypass authentication and gain full administrative control over NETGEAR WiFi range extenders, potentially compromising network security and enabling further attacks.

Affected Products

NETGEAR EX2800 WiFi Range Extender
NETGEAR EX3110 WiFi Range Extender
NETGEAR EX5000 WiFi Range Extender
NETGEAR EX6110 WiFi Range Extender

Discovery Timeline

2026-01-13 - CVE-2026-0407 published to NVD
2026-01-13 - Last updated in NVD database

Technical Details for CVE-2026-0407

Vulnerability Analysis

This authentication bypass vulnerability in NETGEAR WiFi range extenders represents a significant security flaw in the device's access control mechanism. The vulnerability allows an attacker who has already gained network access—either through WiFi authentication to the extended network or via physical connection to an Ethernet port—to bypass the normal authentication process required to access the device's administrative panel.

Once the authentication is bypassed, the attacker gains full administrative privileges on the affected range extender. This access enables modification of device configuration, WiFi credentials, network settings, and potentially allows the attacker to use the compromised device as a pivot point for further attacks within the network.

The adjacent network attack vector means exploitation requires the attacker to be on the same network segment as the target device. This limits remote exploitation but poses a significant risk in shared network environments, such as apartments, offices, or public spaces where multiple users share network infrastructure.

Root Cause

The root cause of this vulnerability is improper authentication implementation (CWE-287) in the administrative web interface of affected NETGEAR WiFi range extenders. The authentication mechanism fails to properly validate user credentials or session tokens under certain conditions, allowing an attacker to access administrative functions without providing valid authentication credentials. This type of flaw typically stems from logic errors in the authentication flow, missing authentication checks on specific endpoints, or improper session management that allows session reuse or bypass.

Attack Vector

The attack requires network adjacency, meaning the attacker must first establish a connection to the network extended by the vulnerable range extender. This can be accomplished through:

WiFi Authentication: Connecting to the extended wireless network using legitimate or compromised WiFi credentials
Physical Access: Connecting directly to an available Ethernet port on the range extender

Once network adjacency is established, the attacker can exploit the authentication bypass vulnerability to access the admin panel. The low attack complexity indicates that exploitation does not require specialized tools or conditions—standard network access and knowledge of the vulnerability are sufficient.

The attack does not require user interaction, making it particularly dangerous as it can be executed silently without alerting legitimate administrators or users of the network.

Detection Methods for CVE-2026-0407

Indicators of Compromise

Unexpected configuration changes on NETGEAR range extenders, including modified WiFi settings, passwords, or network parameters
Unauthorized access attempts or successful logins to the admin panel from unrecognized devices
New or modified DNS settings, static routes, or port forwarding rules that were not configured by administrators
Unusual network traffic patterns originating from or directed to the range extender's management interface

Detection Strategies

Monitor network traffic for HTTP/HTTPS requests to the range extender's administrative interface from unauthorized source IP addresses
Implement network segmentation and monitor cross-segment traffic for attempts to access management interfaces
Deploy network-based intrusion detection systems (NIDS) with signatures for authentication bypass attempts on embedded device interfaces
Maintain configuration baselines for all network infrastructure devices and alert on unauthorized changes

Monitoring Recommendations

Enable logging on the range extender if supported and forward logs to a centralized SIEM for analysis
Implement network access control (NAC) to identify and track all devices connecting to the network
Regularly audit administrative access to network devices and review access logs for anomalies
Consider deploying a network monitoring solution that can detect unauthorized configuration changes on embedded devices

How to Mitigate CVE-2026-0407

Immediate Actions Required

Download and apply the latest firmware updates from NETGEAR for all affected range extender models (EX2800, EX3110, EX5000, EX6110)
Change the default administrative credentials to strong, unique passwords immediately
Restrict physical access to the range extender's Ethernet ports to prevent unauthorized direct connections
Implement network segmentation to isolate management interfaces from general network traffic
Review device configurations for any unauthorized changes and restore from known-good backups if necessary

Patch Information

NETGEAR has released a security advisory addressing this vulnerability. Affected users should visit the NETGEAR Security Advisory January 2026 page to obtain the latest firmware versions and installation instructions.

Firmware updates can be downloaded from the respective product support pages:

Workarounds

Restrict access to the administrative interface by only connecting to it from trusted devices on a secured network segment
Disable remote management features if not required for device administration
Use strong WiFi authentication (WPA3 if supported, or WPA2-PSK with a complex passphrase) to limit network access to authorized users only
Consider placing management interfaces on a separate VLAN with strict access controls
Monitor for and disconnect any unknown devices that appear on the network

bash

# Network segmentation example for isolating management interfaces
# Add firewall rules to restrict admin panel access (adjust for your firewall)
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP