CVE-2026-4488: UTT HiPER 1250GW Buffer Overflow Flaw

CVE-2026-4488 Overview

A buffer overflow vulnerability has been identified in UTT HiPER 1250GW routers up to version 3.2.7-210907-180535. The vulnerability affects the strcpy function within the file /goform/setSysAdm, where improper handling of the GroupName argument allows an attacker to trigger a buffer overflow condition. This vulnerability can be exploited remotely over the network, potentially leading to arbitrary code execution or denial of service on affected devices.

Critical Impact

Remote attackers can exploit this buffer overflow vulnerability to potentially execute arbitrary code or crash the device, compromising network security and availability.

Affected Products

• UTT HiPER 1250GW up to version 3.2.7-210907-180535

Discovery Timeline

• 2026-03-20 - CVE-2026-4488 published to NVD
• 2026-03-24 - Last updated in NVD database

Technical Details for CVE-2026-4488

Vulnerability Analysis

This vulnerability falls under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). The root issue lies in the unsafe use of the strcpy function when processing the GroupName parameter in the /goform/setSysAdm endpoint. The strcpy function does not perform bounds checking, making it susceptible to buffer overflow when user-supplied input exceeds the allocated buffer size.

The vulnerability is remotely exploitable over the network and requires low privileges to trigger. Once exploited, an attacker could achieve high impact on confidentiality, integrity, and availability of the affected device.

Root Cause

The root cause of this vulnerability is the use of the unsafe strcpy function to copy user-controlled input (GroupName parameter) into a fixed-size buffer without proper bounds checking. When the GroupName value exceeds the expected buffer length, it overwrites adjacent memory, leading to a classic stack-based or heap-based buffer overflow condition.

This is a common vulnerability pattern in embedded devices and IoT firmware where legacy C functions are used without proper input validation or safe alternatives like strncpy or strlcpy.

Attack Vector

The attack can be launched remotely over the network by sending a crafted HTTP request to the /goform/setSysAdm endpoint with an oversized GroupName parameter. The attacker needs low-level authentication to access this endpoint.

The exploitation mechanism involves:

1. An attacker sends an HTTP POST request to the /goform/setSysAdm form handler
2. The request includes a maliciously crafted GroupName parameter with a value exceeding the expected buffer size
3. The vulnerable strcpy function copies this oversized input into a fixed-size buffer
4. The overflow corrupts adjacent memory, potentially overwriting return addresses or function pointers
5. This can lead to arbitrary code execution, device crash, or other undefined behavior

For technical details and additional documentation, refer to the GitHub HiPER Documentation and VulDB entry #352011.

Detection Methods for CVE-2026-4488

Indicators of Compromise

• Unusual HTTP POST requests to /goform/setSysAdm containing abnormally long GroupName parameter values
• Device crashes or unexpected reboots following administrative form submissions
• Anomalous network traffic patterns targeting the router's web management interface
• Evidence of unauthorized configuration changes on the affected device

Detection Strategies

• Monitor HTTP traffic for POST requests to /goform/setSysAdm with GroupName parameters exceeding typical length (e.g., greater than 256 characters)
• Implement network intrusion detection rules to flag buffer overflow attack patterns targeting UTT HiPER devices
• Review web server logs on the device for malformed or oversized form submissions
• Deploy endpoint detection on network segments to identify exploitation attempts

Monitoring Recommendations

• Enable verbose logging on the UTT HiPER 1250GW web management interface if available
• Set up network monitoring to track access to the router's administrative endpoints
• Configure alerts for repeated failed authentication attempts or unusual administrative actions
• Regularly review device stability logs for unexpected crashes or restarts

How to Mitigate CVE-2026-4488

Immediate Actions Required

• Restrict network access to the web management interface of affected UTT HiPER 1250GW devices
• Implement firewall rules to block external access to the /goform/setSysAdm endpoint
• Place affected devices behind a VPN or internal network segment with strict access controls
• Monitor for vendor security updates and apply patches as soon as available

Patch Information

At the time of publication, no official patch information has been made available by the vendor. Organizations should monitor the VulDB entry and vendor communications for security update announcements. Users are advised to contact UTT directly for remediation guidance.

Workarounds

• Disable remote management access to the UTT HiPER 1250GW web interface if not required
• Implement network segmentation to isolate affected devices from untrusted networks
• Use a web application firewall (WAF) or reverse proxy to filter and validate input to the administrative interface
• Consider replacing affected devices with models from vendors that have active security update programs

# Example firewall rule to restrict access to management interface
# Block external access to web management on affected device
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