CVE-2025-15429: UTT 进取 512W Buffer Overflow Vulnerability

CVE-2025-15429 Overview

A buffer overflow vulnerability has been identified in UTT 进取 512W firmware version 1.7.7-171114. The vulnerability exists in the strcpy function within the /goform/formConfigCliForEngineerOnly endpoint, where improper handling of the addCommand argument allows an attacker to overflow a buffer and potentially execute arbitrary code. This vulnerability can be exploited remotely over the network, making it particularly dangerous for exposed devices. The exploit has been publicly disclosed, and the vendor was contacted but did not respond.

Critical Impact

Remote attackers can exploit this buffer overflow vulnerability to achieve code execution, potentially gaining complete control over affected UTT 进取 512W routers. This could lead to network compromise, data interception, or use of the device in botnet attacks.

Affected Products

• UTT 进取 512W firmware version 1.7.7-171114

Discovery Timeline

• 2026-01-02 - CVE-2025-15429 published to NVD
• 2026-01-02 - Last updated in NVD database

Technical Details for CVE-2025-15429

Vulnerability Analysis

This vulnerability is a classic stack-based buffer overflow (CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer) affecting the UTT 进取 512W router's web management interface. The vulnerable endpoint /goform/formConfigCliForEngineerOnly is designed for engineer-level configuration but fails to properly validate input length before copying user-supplied data.

The flaw occurs when the strcpy function is used to copy attacker-controlled input from the addCommand parameter into a fixed-size buffer without performing bounds checking. Since strcpy does not verify the destination buffer can accommodate the source string, an attacker can supply a malicious payload that exceeds the buffer's allocated size, overwriting adjacent memory including the return address on the stack.

Successful exploitation requires low-privilege authentication to the router's web interface but does not require user interaction. An attacker can potentially achieve arbitrary code execution with the privileges of the web server process, typically running as root on embedded devices.

Root Cause

The root cause is the use of the unsafe strcpy function to handle user-controlled input without prior length validation. The addCommand parameter passed to /goform/formConfigCliForEngineerOnly is copied directly into a stack buffer using strcpy, which does not perform bounds checking. Secure alternatives such as strncpy or snprintf with proper size limits should be used to prevent buffer overflow conditions.

Attack Vector

The attack can be executed remotely over the network by any authenticated user with access to the router's web management interface. The attacker crafts a malicious HTTP request to the /goform/formConfigCliForEngineerOnly endpoint with an oversized addCommand parameter. When processed by the vulnerable firmware, the overflow overwrites critical stack data, allowing the attacker to redirect program execution to shellcode or return-oriented programming (ROP) gadgets.

The vulnerability mechanism involves the following sequence:

1. The attacker authenticates to the router's web interface with low-privilege credentials
2. A crafted HTTP POST request is sent to /goform/formConfigCliForEngineerOnly with an oversized addCommand parameter
3. The strcpy function copies the malicious input into a fixed-size stack buffer
4. The buffer overflow corrupts the stack, overwriting the return address
5. Upon function return, execution is redirected to attacker-controlled code

For technical details and proof-of-concept information, refer to the GitHub PoC Documentation.

Detection Methods for CVE-2025-15429

Indicators of Compromise

• Anomalous HTTP POST requests to /goform/formConfigCliForEngineerOnly with unusually large addCommand parameters
• Unexpected crashes or reboots of UTT 进取 512W routers
• Suspicious outbound network connections from the router to unknown IP addresses
• Unauthorized configuration changes or new user accounts on the device

Detection Strategies

• Deploy web application firewall (WAF) rules to detect and block requests with oversized parameters to the /goform/formConfigCliForEngineerOnly endpoint
• Implement network intrusion detection signatures to identify buffer overflow exploitation patterns targeting this endpoint
• Monitor authentication logs for brute-force attempts against the router's management interface
• Enable logging on upstream firewalls to capture all traffic to/from the router's management interface

Monitoring Recommendations

• Configure alerts for any access to engineering-level configuration endpoints on UTT routers
• Establish baseline network behavior for the router and alert on deviations indicating compromise
• Regularly audit device configurations for unauthorized changes
• Monitor for firmware modification attempts or unexpected file system changes

How to Mitigate CVE-2025-15429

Immediate Actions Required

• Restrict access to the router's web management interface to trusted IP addresses only using firewall rules
• Disable remote management if not strictly required
• Implement network segmentation to isolate the router from untrusted network segments
• Monitor for exploitation attempts using the detection strategies outlined above

Patch Information

No official patch is currently available from the vendor. According to the vulnerability disclosure, the vendor was contacted but did not respond. Organizations should consider the following alternatives:

• Contact UTT directly to inquire about firmware updates or security patches
• Evaluate replacing affected devices with actively maintained alternatives
• Reference VulDB #339351 for ongoing updates regarding this vulnerability

Workarounds

• Implement strict firewall rules to limit management interface access to specific trusted IP addresses
• Use a VPN for remote administration rather than exposing the management interface directly
• Deploy an upstream web application firewall to filter malicious requests targeting the vulnerable endpoint
• Consider deploying the router behind a reverse proxy that can validate and sanitize input parameters

# Example firewall rule to restrict management interface access (iptables)
# Only allow management access from trusted admin network 192.168.1.0/24
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