CVE-2026-3168: Tenda F453 Buffer Overflow Vulnerability

CVE-2026-3168 Overview

A buffer overflow vulnerability has been identified in the Tenda F453 router firmware version 1.0.0.3. This vulnerability affects the fromNatStaticSetting function within the /goform/NatStaticSetting endpoint of the httpd component. By manipulating the page argument, an attacker can trigger a buffer overflow condition. The attack can be launched remotely, and exploit information has been made publicly available, increasing the risk of active exploitation.

Critical Impact

Remote attackers can exploit this buffer overflow vulnerability to potentially achieve code execution on affected Tenda F453 routers, compromising network security and enabling further attacks on connected devices.

Affected Products

• Tenda F453 Firmware version 1.0.0.3
• Tenda F453 Hardware

Discovery Timeline

• 2026-02-25 - CVE-2026-3168 published to NVD
• 2026-02-25 - Last updated in NVD database

Technical Details for CVE-2026-3168

Vulnerability Analysis

This vulnerability is classified as CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). The affected function fromNatStaticSetting in the httpd web server component fails to properly validate the bounds of the page argument before processing it. This improper memory bounds handling allows an attacker to write data beyond the allocated buffer, potentially corrupting adjacent memory regions.

The vulnerability is accessible via the network through the /goform/NatStaticSetting endpoint, requiring only low-level privileges to exploit. No user interaction is required for successful exploitation, making it particularly dangerous for exposed devices.

Root Cause

The root cause of this vulnerability lies in insufficient input validation and bounds checking within the fromNatStaticSetting function. When processing the page parameter from HTTP requests, the function does not adequately verify the size of the input data before copying it into a fixed-size buffer. This classic buffer overflow pattern allows memory corruption when oversized input is provided.

Attack Vector

The attack can be executed remotely over the network by sending a crafted HTTP request to the /goform/NatStaticSetting endpoint on the affected device. The attacker manipulates the page argument with specially crafted data designed to overflow the target buffer. Successful exploitation could lead to:

• Denial of service by crashing the httpd service
• Potential arbitrary code execution with the privileges of the web server process
• Complete device compromise, enabling persistent access to the router

The vulnerability mechanism involves sending malformed HTTP requests to the affected endpoint. The page parameter is processed by the fromNatStaticSetting function without adequate bounds checking, allowing an attacker to overflow the internal buffer. For detailed technical analysis, refer to the GitHub Vulnerability Documentation.

Detection Methods for CVE-2026-3168

Indicators of Compromise

• Unusual HTTP POST requests to /goform/NatStaticSetting with abnormally large or malformed page parameter values
• Unexpected crashes or restarts of the httpd service on Tenda F453 devices
• Suspicious network traffic patterns targeting the router's web management interface
• Anomalous memory usage or system instability on affected devices

Detection Strategies

• Implement network intrusion detection rules to identify HTTP requests containing oversized page parameters to /goform/NatStaticSetting
• Monitor web server logs on Tenda devices for malformed or suspicious request patterns
• Deploy SentinelOne Singularity to detect buffer overflow exploitation attempts and anomalous process behavior on network infrastructure

Monitoring Recommendations

• Enable logging on Tenda F453 routers and regularly review logs for suspicious activity
• Implement network segmentation to limit exposure of router management interfaces
• Use network traffic analysis tools to monitor for exploitation attempts against IoT and router devices

How to Mitigate CVE-2026-3168

Immediate Actions Required

• Restrict access to the Tenda F453 web management interface to trusted networks only
• Implement firewall rules to block external access to port 80/443 on affected devices
• Consider taking affected devices offline until a patch is available if they are exposed to untrusted networks
• Monitor the Tenda Official Website for firmware updates addressing this vulnerability

Patch Information

At the time of publication, no official patch has been released by Tenda for this vulnerability. Organizations should monitor vendor communications and apply firmware updates as soon as they become available. Additional technical details can be found in the VulDB entry #347675.

Workarounds

• Disable remote web management access and only allow administration from the local network
• Place the Tenda F453 behind a firewall that restricts access to the management interface
• Implement network access controls to limit which IP addresses can reach the device's web interface
• Consider replacing affected devices with alternatives that have better security update support

# Example firewall rule to restrict access to router management interface
# Block external access to Tenda router web interface (adjust IP as needed)
iptables -A INPUT -p tcp --dport 80 -s ! 192.168.1.0/24 -j DROP
iptables -A INPUT -p tcp --dport 443 -s ! 192.168.1.0/24 -j DROP