CVE-2025-15431: UTT 进取 512W Buffer Overflow Vulnerability

CVE-2025-15431 Overview

A buffer overflow vulnerability has been identified in UTT 进取 512W router firmware version 1.7.7-171114. This critical flaw affects the strcpy function within the /goform/formFtpServerDirConfig endpoint. Attackers can exploit this vulnerability by manipulating the filename argument, leading to a classic buffer overflow condition that can be triggered remotely over the network.

The vulnerability stems from improper bounds checking when handling user-supplied input, allowing attackers to overwrite adjacent memory and potentially achieve code execution on the affected device. The vendor was contacted early about this disclosure but did not respond in any way.

Critical Impact

Remote attackers can exploit this buffer overflow vulnerability to potentially execute arbitrary code or cause denial of service on affected UTT 进取 512W routers, compromising network security.

Affected Products

• UTT 进取 512W Router Firmware Version 1.7.7-171114
• Devices running the vulnerable /goform/formFtpServerDirConfig endpoint

Discovery Timeline

• 2026-01-02 - CVE-2025-15431 published to NVD
• 2026-01-02 - Last updated in NVD database

Technical Details for CVE-2025-15431

Vulnerability Analysis

This vulnerability is classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). The flaw exists in the FTP server directory configuration handler of the UTT router's web management interface.

The vulnerable code path involves the strcpy function processing user-controlled input from the filename parameter without adequate length validation. When an attacker submits a specially crafted request to the /goform/formFtpServerDirConfig endpoint with an oversized filename value, the strcpy function blindly copies this data into a fixed-size buffer, causing memory corruption.

This memory corruption can lead to multiple security impacts including denial of service through application crashes, and potentially remote code execution if the attacker can control the overwritten memory addresses to redirect program execution flow.

Root Cause

The root cause of CVE-2025-15431 is the unsafe use of the strcpy function to copy user-supplied data without implementing proper bounds checking. The strcpy function is inherently dangerous as it copies data until a null terminator is encountered, without considering the destination buffer size. When the filename argument exceeds the allocated buffer space, adjacent memory regions are overwritten, leading to memory corruption and potentially controllable program behavior.

Attack Vector

The attack can be launched remotely over the network by sending malicious HTTP requests to the vulnerable endpoint. An attacker with low-privilege access to the router's web interface can craft a request to /goform/formFtpServerDirConfig containing an excessively long filename parameter value. The attack requires no user interaction and can be executed directly against exposed router management interfaces.

The vulnerability is accessible via the network attack vector, meaning any attacker who can reach the router's web management interface can attempt exploitation. This is particularly concerning for routers with internet-exposed management interfaces or in scenarios where attackers have already gained access to the local network.

Technical details and proof-of-concept information can be found in the GitHub CVE Documentation and VulDB CVE Analysis.

Detection Methods for CVE-2025-15431

Indicators of Compromise

• Unusual HTTP POST requests to /goform/formFtpServerDirConfig with abnormally long filename parameters
• Router crashes or unexpected reboots potentially indicating exploitation attempts
• Anomalous network traffic patterns targeting the router's web management interface
• Evidence of memory corruption or buffer overflow payloads in web server logs

Detection Strategies

• Implement network intrusion detection rules to identify requests to /goform/formFtpServerDirConfig containing oversized parameters
• Monitor for HTTP requests with filename parameter values exceeding typical length thresholds
• Deploy web application firewall rules to filter requests containing potential buffer overflow patterns
• Enable logging on router management interfaces to capture suspicious access attempts

Monitoring Recommendations

• Audit access logs for the router's web management interface regularly
• Implement rate limiting on web management endpoints to slow exploitation attempts
• Configure alerts for repeated access to /goform/formFtpServerDirConfig from unusual sources
• Monitor router stability and investigate unexpected restarts or crashes

How to Mitigate CVE-2025-15431

Immediate Actions Required

• Restrict access to the router's web management interface to trusted IP addresses only
• Disable remote management access if not required
• Place affected devices behind a firewall that filters incoming traffic to management interfaces
• Monitor for exploitation attempts while awaiting a vendor patch

Patch Information

No official patch is currently available from the vendor. According to disclosure information, the vendor was contacted about this vulnerability but did not respond. Organizations using affected UTT 进取 512W devices should implement workarounds and monitor for any future firmware updates.

For additional technical information, refer to the VulDB entry #339353 and the GitHub PoC Repository.

Workarounds

• Implement firewall rules to block external access to the router management interface
• Configure network ACLs to limit management interface access to specific administrative IP addresses
• Consider replacing affected devices with alternatives that receive regular security updates
• If the device must remain in service, isolate it on a separate network segment with strict access controls

# Example firewall rule to restrict management access (adapt for your environment)
# Block external access to router management port
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