CVE-2025-15047: Tenda WH450 Buffer Overflow Vulnerability

CVE-2025-15047 Overview

A stack-based buffer overflow vulnerability has been identified in the Tenda WH450 wireless router firmware version 1.0.0.18. This vulnerability exists within the HTTP Request Handler component, specifically in the /goform/PPTPDClient endpoint. By manipulating the Username argument, an unauthenticated remote attacker can trigger a buffer overflow condition that could lead to arbitrary code execution or denial of service on the affected device.

Critical Impact

This vulnerability allows remote attackers to exploit a stack-based buffer overflow without authentication, potentially enabling complete device compromise, arbitrary code execution, or service disruption on Tenda WH450 routers.

Affected Products

• Tenda WH450 Firmware version 1.0.0.18
• Tenda WH450 Hardware

Discovery Timeline

• 2025-12-23 - CVE-2025-15047 published to NVD
• 2026-02-24 - Last updated in NVD database

Technical Details for CVE-2025-15047

Vulnerability Analysis

This vulnerability is classified as CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), which indicates insufficient boundary checks when handling user-supplied input. The vulnerable endpoint /goform/PPTPDClient is part of the device's web management interface and processes PPTP (Point-to-Point Tunneling Protocol) client configuration requests.

When the Username parameter is submitted to this endpoint, the firmware fails to properly validate the length of the input before copying it to a fixed-size stack buffer. This allows an attacker to provide an excessively long username value that exceeds the buffer's allocated space, overwriting adjacent memory on the stack including potentially critical data such as return addresses and saved registers.

The network-accessible nature of this vulnerability combined with no authentication requirements makes it particularly dangerous for devices exposed to untrusted networks. Successful exploitation could grant an attacker full control over the router, enabling network traffic interception, configuration manipulation, or using the compromised device as a pivot point for further attacks.

Root Cause

The root cause of this vulnerability stems from improper input validation in the HTTP Request Handler's processing of the Username argument within the PPTP client configuration functionality. The firmware uses an unsafe memory operation (likely strcpy or similar function) to copy user-supplied data into a stack-allocated buffer without verifying that the input length does not exceed the buffer's capacity. This lack of bounds checking creates a classic stack-based buffer overflow condition.

Attack Vector

The attack can be initiated remotely over the network by sending a specially crafted HTTP POST request to the /goform/PPTPDClient endpoint on the Tenda WH450's web management interface. The attacker includes an oversized Username parameter value designed to overflow the stack buffer. No authentication is required to access this endpoint, making exploitation straightforward for any attacker with network access to the device's management interface.

The vulnerability mechanism can be described as follows: The HTTP request handler receives the POST request and extracts the Username parameter value. This value is then copied into a fixed-size stack buffer without length validation. When the supplied data exceeds the buffer size, it overwrites adjacent stack memory, potentially including the function's return address. An attacker can craft the overflow payload to redirect execution flow to attacker-controlled code or cause a denial of service.

Technical details and reproduction steps are available in the GitHub PoC Repository.

Detection Methods for CVE-2025-15047

Indicators of Compromise

• Unusual HTTP POST requests to /goform/PPTPDClient containing abnormally long Username parameter values
• Unexpected router reboots or crashes that may indicate exploitation attempts
• Unexplained changes to router configuration settings
• Network traffic anomalies originating from the router device

Detection Strategies

• Monitor HTTP traffic to the router's web management interface for requests targeting /goform/PPTPDClient with oversized parameters
• Implement network intrusion detection rules to alert on POST requests containing excessively long Username fields (typically exceeding several hundred bytes)
• Deploy SentinelOne Singularity for IoT to monitor firmware behavior and detect exploitation attempts against network devices

Monitoring Recommendations

• Enable logging on network firewalls to capture traffic directed at router management interfaces
• Implement network segmentation to isolate IoT and network infrastructure devices from untrusted networks
• Deploy continuous network monitoring solutions to detect anomalous traffic patterns targeting embedded devices

How to Mitigate CVE-2025-15047

Immediate Actions Required

• Restrict access to the Tenda WH450 web management interface to trusted networks only
• Implement firewall rules to block external access to ports used by the device's web interface
• Consider disabling the PPTP client functionality if not required
• Monitor for any available firmware updates from Tenda

Patch Information

As of the last NVD update on 2026-02-24, no official patch information has been published by Tenda for this vulnerability. Organizations should monitor the Tenda Official Website for security advisories and firmware updates. Additional vulnerability tracking information is available at VulDB #337852.

Workarounds

• Implement access control lists (ACLs) on upstream network devices to restrict management interface access to authorized IP addresses only
• Place the Tenda WH450 behind a firewall that blocks inbound connections to the web management port
• Disable remote management features if not operationally required
• Consider replacing end-of-life or unsupported network devices with actively maintained alternatives

# Example iptables rule to restrict management interface access
# Replace 192.168.1.0/24 with your trusted management network
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP