CVE-2024-30584: Tenda FH1202 Buffer Overflow Vulnerability

CVE-2024-30584 Overview

CVE-2024-30584 is a stack overflow vulnerability affecting Tenda FH1202 wireless routers running firmware version 1.2.0.14(408). The vulnerability exists in the security parameter of the formWifiBasicSet function, which fails to properly validate input length before copying data to a stack buffer. This allows remote attackers to potentially execute arbitrary code or cause denial of service conditions on affected devices.

Critical Impact

This stack overflow vulnerability allows unauthenticated remote attackers to compromise Tenda FH1202 routers via network-accessible interfaces, potentially leading to complete device takeover, network infiltration, or persistent denial of service.

Affected Products

• Tenda FH1202 Hardware Device
• Tenda FH1202 Firmware version 1.2.0.14(408)

Discovery Timeline

• 2024-03-28 - CVE-2024-30584 published to NVD
• 2025-03-13 - Last updated in NVD database

Technical Details for CVE-2024-30584

Vulnerability Analysis

This vulnerability is classified as CWE-120 (Buffer Copy without Checking Size of Input), a classic memory corruption flaw commonly found in embedded systems and IoT devices. The formWifiBasicSet function in the Tenda FH1202 firmware processes user-supplied input through the security parameter without adequate bounds checking before copying it to a fixed-size stack buffer.

When an attacker supplies a maliciously crafted value for the security parameter that exceeds the expected buffer size, the overflow corrupts adjacent memory on the stack. This can overwrite critical control structures including saved return addresses and frame pointers, potentially allowing an attacker to redirect program execution to attacker-controlled memory regions.

The vulnerability is particularly dangerous because it is network-accessible without authentication requirements, meaning any attacker with network access to the router's management interface can attempt exploitation.

Root Cause

The root cause of CVE-2024-30584 is improper input validation in the formWifiBasicSet function. The function receives user input through the security parameter but fails to verify that the input length does not exceed the allocated stack buffer size before performing a copy operation. This represents a fundamental secure coding failure where external input is trusted without validation, allowing attackers to write beyond buffer boundaries.

Attack Vector

The attack vector for this vulnerability is network-based, requiring no authentication or user interaction. An attacker can exploit this vulnerability by sending a specially crafted HTTP request to the router's web management interface containing an oversized value for the security parameter in the formWifiBasicSet function handler.

The exploitation scenario involves:

1. Attacker identifies a Tenda FH1202 router running vulnerable firmware version 1.2.0.14(408) on the network
2. Attacker crafts an HTTP request to the formWifiBasicSet endpoint with an oversized security parameter value
3. The malformed input triggers the stack buffer overflow, corrupting memory and potentially overwriting the return address
4. Upon function return, execution may be redirected to attacker-controlled code, enabling arbitrary command execution on the device

Technical details regarding the specific exploitation methodology can be found in the GitHub IoT Vulnerability Report.

Detection Methods for CVE-2024-30584

Indicators of Compromise

• Unexpected device reboots or crashes indicating memory corruption attempts
• Unusual network traffic patterns targeting router management ports (typically HTTP/HTTPS)
• HTTP requests with abnormally long parameter values in web server logs
• Unauthorized configuration changes or new administrative accounts on the router
• Suspicious outbound connections from the router to unknown external IP addresses

Detection Strategies

• Monitor HTTP traffic to Tenda FH1202 devices for requests containing oversized security parameter values
• Implement network-based intrusion detection signatures for stack overflow exploitation patterns targeting embedded devices
• Deploy network segmentation to isolate IoT devices and monitor traffic crossing segment boundaries
• Conduct regular firmware version audits to identify devices running vulnerable firmware 1.2.0.14(408)

Monitoring Recommendations

• Enable logging on network firewalls and IDS/IPS systems for traffic to router management interfaces
• Implement anomaly detection for HTTP requests with parameter lengths exceeding normal thresholds
• Monitor for unexpected process crashes or watchdog timer resets on Tenda devices if console access is available
• Establish baseline network behavior for router devices and alert on deviations

How to Mitigate CVE-2024-30584

Immediate Actions Required

• Restrict network access to the router's web management interface to trusted administrative hosts only
• Disable remote management features if not required for operations
• Segment the network to isolate vulnerable Tenda FH1202 devices from untrusted networks
• Monitor for exploitation attempts using network-based security controls
• Consider replacing end-of-life devices if no firmware update is available from the vendor

Patch Information

At the time of this analysis, no official patch information has been published by Tenda for CVE-2024-30584. Organizations should monitor Tenda's official support channels for firmware updates addressing this vulnerability. Given the severity of this flaw, upgrading to a patched firmware version when available should be treated as a high priority.

Workarounds

• Implement access control lists (ACLs) on upstream network devices to restrict access to the router's management interface to authorized IP addresses only
• Disable the web management interface entirely if not operationally required
• Deploy a web application firewall (WAF) or reverse proxy with input validation rules to filter requests with oversized parameters
• Consider network isolation by placing vulnerable devices behind additional security controls

# Example: Restrict management access via upstream firewall (iptables)
# Block external access to router management port
iptables -A FORWARD -d <router_ip> -p tcp --dport 80 -j DROP
iptables -A FORWARD -d <router_ip> -p tcp --dport 443 -j DROP

# Allow management access only from trusted admin workstation
iptables -I FORWARD -s <admin_ip> -d <router_ip> -p tcp --dport 80 -j ACCEPT