CVE-2025-15462: UTT 进取 520W Buffer Overflow Vulnerability

CVE-2025-15462 Overview

A buffer overflow vulnerability has been discovered in UTT 进取 520W router firmware version 1.7.7-180627. The vulnerability exists in the strcpy function within the /goform/ConfigAdvideo endpoint. Exploitation occurs through manipulation of the timestart argument, which can lead to a buffer overflow condition. This vulnerability is remotely exploitable over the network by an authenticated attacker, potentially allowing for complete compromise of the affected device.

Critical Impact

Remote attackers with low-privilege access can exploit this buffer overflow to potentially achieve code execution, compromising the confidentiality, integrity, and availability of the router. The vendor was contacted but did not respond to the disclosure.

Affected Products

• UTT 进取 520W Router Firmware Version 1.7.7-180627

Discovery Timeline

• 2026-01-05 - CVE-2025-15462 published to NVD
• 2026-01-08 - Last updated in NVD database

Technical Details for CVE-2025-15462

Vulnerability Analysis

This vulnerability is classified as CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). The core issue stems from the unsafe use of the strcpy function when processing user-supplied input through the timestart parameter in the /goform/ConfigAdvideo endpoint.

The strcpy function does not perform bounds checking, which means that if an attacker provides a timestart argument exceeding the expected buffer size, the function will write beyond the allocated memory region. This can corrupt adjacent memory structures, potentially leading to arbitrary code execution or denial of service conditions.

The vulnerability is exploitable remotely over the network, requiring only low-privilege authentication. No user interaction is required for exploitation. A proof-of-concept exploit has been publicly disclosed, increasing the risk of active exploitation in the wild.

Root Cause

The root cause of this vulnerability is the use of the unsafe strcpy function without proper input validation or length checking. The firmware fails to sanitize or validate the length of the timestart parameter before copying it into a fixed-size buffer. This is a classic memory safety issue that could have been prevented by using safer string handling functions such as strncpy or implementing proper input validation.

Attack Vector

The attack vector is network-based, targeting the /goform/ConfigAdvideo endpoint on affected UTT 进取 520W routers. An attacker with valid low-privilege credentials can craft a malicious HTTP request containing an oversized timestart parameter value. When the vulnerable strcpy function processes this input, the buffer overflow occurs, potentially allowing the attacker to overwrite critical memory regions including return addresses or function pointers.

Successful exploitation could allow an attacker to execute arbitrary code with the privileges of the web server process, typically running as root on embedded devices. This could lead to complete device compromise, including the ability to intercept network traffic, modify router configurations, or use the device as a pivot point for further attacks.

Detection Methods for CVE-2025-15462

Indicators of Compromise

• Unusual HTTP POST requests to /goform/ConfigAdvideo with abnormally large timestart parameter values
• Unexpected router reboots or crashes that may indicate exploitation attempts
• Unauthorized configuration changes on affected UTT 520W routers
• Anomalous network traffic patterns originating from the router's management interface

Detection Strategies

• Monitor HTTP traffic to UTT 520W routers for requests to /goform/ConfigAdvideo containing timestart parameters exceeding normal length thresholds
• Implement network intrusion detection rules to alert on potential buffer overflow exploitation patterns targeting this endpoint
• Review router access logs for repeated authentication attempts followed by POST requests to the vulnerable endpoint
• Deploy web application firewall rules to block requests with oversized parameters to router management interfaces

Monitoring Recommendations

• Enable verbose logging on UTT 520W routers if available to capture web interface access attempts
• Configure network monitoring tools to alert on unexpected traffic patterns to router management ports
• Regularly audit router configurations for unauthorized changes that may indicate compromise
• Monitor for unusual outbound connections from router devices that could indicate post-exploitation activity

How to Mitigate CVE-2025-15462

Immediate Actions Required

• Restrict network access to the router's web management interface to trusted IP addresses only
• Disable remote management functionality if not required for operations
• Place affected routers behind a firewall that can filter and inspect HTTP traffic
• Monitor for exploitation attempts while awaiting a vendor patch

Patch Information

No patch is currently available from the vendor. According to the disclosure, the vendor (UTT) was contacted early about this vulnerability but did not respond. Organizations should monitor the VulDB entry and vendor channels for any future security updates. Consider replacing vulnerable devices with alternative products if the vendor does not provide a timely fix.

Workarounds

• Disable the web management interface entirely and manage the router through alternative methods if available
• Implement strict access control lists (ACLs) to limit which IP addresses can access the management interface
• Deploy a reverse proxy or web application firewall in front of the router management interface to filter malicious requests
• Consider network segmentation to isolate vulnerable routers from untrusted network segments

# Example firewall rule to restrict access to router management interface
# Replace 192.168.1.1 with the router's IP and 192.168.1.100 with trusted admin IP
iptables -A FORWARD -d 192.168.1.1 -p tcp --dport 80 -s 192.168.1.100 -j ACCEPT
iptables -A FORWARD -d 192.168.1.1 -p tcp --dport 80 -j DROP