CVE-2026-24429: Tenda W30e Auth Bypass Vulnerability

CVE-2026-24429 Overview

CVE-2026-24429 is a critical hardcoded credentials vulnerability affecting Shenzhen Tenda W30E V2 firmware versions up to and including V16.01.0.19(5037). The firmware ships with a predefined default password for a built-in authentication account that is not required to be changed during initial configuration. An attacker can leverage these default credentials to gain authenticated access to the management interface, potentially leading to full device compromise.

Critical Impact

Attackers with network access can exploit default credentials to gain full administrative control over the device, enabling configuration changes, network traffic manipulation, and potential use of the device as a pivot point for further attacks.

Affected Products

• Tenda W30E V2 hardware device
• Tenda W30E firmware versions up to and including V16.01.0.19(5037)
• All deployments using factory default configurations

Discovery Timeline

• 2026-01-26 - CVE-2026-24429 published to NVD
• 2026-01-29 - Last updated in NVD database

Technical Details for CVE-2026-24429

Vulnerability Analysis

This vulnerability is classified under CWE-1393 (Use of Default Password), representing a fundamental security design flaw in the Tenda W30E V2 router firmware. The device ships with a built-in authentication account containing a predefined default password that persists unless manually changed by the administrator.

The critical nature of this vulnerability stems from the combination of network accessibility and the lack of mandatory password change requirements during initial device setup. Once deployed on a network, the device's management interface becomes accessible to any attacker who can reach it, and the default credentials provide immediate authenticated access without requiring any exploitation complexity.

Root Cause

The root cause of this vulnerability lies in insecure default configuration practices within the Tenda W30E V2 firmware. The firmware includes a hardcoded default password for administrative access that:

1. Is not unique to each device
2. Does not require mandatory change during initial setup
3. Remains valid indefinitely if not manually modified
4. Provides full administrative privileges to the management interface

This design decision prioritizes ease of deployment over security, leaving devices vulnerable in scenarios where administrators fail to implement proper credential hygiene.

Attack Vector

The attack vector is network-based and requires no user interaction or prior privileges. An attacker can exploit this vulnerability by:

1. Identifying Tenda W30E V2 devices on the network through banner grabbing or service fingerprinting
2. Accessing the device's web-based management interface
3. Authenticating using the well-known default credentials
4. Gaining full administrative access to the device configuration

The management interface is typically accessible via HTTP/HTTPS on the device's IP address. Once authenticated, an attacker can modify network configurations, intercept traffic, create backdoor accounts, update firmware with malicious versions, or disable security features.

For technical details regarding the specific default credentials and exploitation methodology, refer to the VulnCheck Advisory.

Detection Methods for CVE-2026-24429

Indicators of Compromise

• Successful authentication events to the management interface from unauthorized IP addresses
• Configuration changes made outside of approved maintenance windows
• New administrative accounts created on the device
• Modified firewall rules or network routing configurations
• Unusual outbound connections originating from the router

Detection Strategies

• Implement network monitoring to detect authentication attempts to Tenda W30E management interfaces
• Deploy intrusion detection rules to identify access attempts using known default credentials
• Conduct regular audits of device configurations to identify unauthorized changes
• Monitor for unexpected firmware updates or configuration exports

Monitoring Recommendations

• Enable logging on all network devices and forward logs to a centralized SIEM
• Configure alerts for successful administrative logins from non-whitelisted IP addresses
• Implement regular vulnerability scanning to identify devices still using default credentials
• Monitor network traffic patterns for anomalous behavior originating from router devices

How to Mitigate CVE-2026-24429

Immediate Actions Required

• Change the default password on all Tenda W30E V2 devices immediately
• Implement strong, unique passwords for each device using at least 12 characters with complexity requirements
• Restrict management interface access to authorized IP addresses only
• Disable remote management if not explicitly required
• Conduct an inventory audit to identify all affected devices in the environment

Patch Information

At the time of publication, no vendor patch has been released that addresses the mandatory password change requirement. Organizations should refer to the Tenda Product Page for potential firmware updates and the VulnCheck Advisory for the latest remediation guidance.

Workarounds

• Implement network segmentation to isolate management interfaces from general network traffic
• Deploy a firewall rule to restrict access to the device management interface from trusted administrative networks only
• Consider using a VPN for all remote administrative access to network devices
• Implement multi-factor authentication at the network perimeter level if direct device MFA is not available
• Deploy network access control (NAC) to limit device accessibility

# Example firewall rule to restrict management access (iptables)
# Replace 192.168.1.1 with your Tenda W30E IP and 10.0.0.0/24 with your admin network
iptables -A INPUT -p tcp --dport 80 -d 192.168.1.1 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -d 192.168.1.1 -j DROP
iptables -A INPUT -p tcp --dport 443 -d 192.168.1.1 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -d 192.168.1.1 -j DROP