CVE-2026-2980: Utt 810g Firmware Buffer Overflow Flaw

CVE-2026-2980 Overview

A critical buffer overflow vulnerability has been discovered in UTT HiPER 810G network devices running firmware versions up to 1.7.7-1711. The vulnerability exists in the strcpy function within the /goform/setSysAdm endpoint, where improper handling of the passwd1 argument allows for memory corruption through buffer overflow attacks. This flaw can be exploited remotely, potentially leading to complete device compromise, unauthorized code execution, and network infrastructure takeover.

Critical Impact

Remote attackers with high privileges can exploit this buffer overflow to achieve arbitrary code execution on affected UTT HiPER 810G devices, potentially compromising network infrastructure security.

Affected Products

• UTT HiPER 810G Firmware versions up to 1.7.7-1711
• UTT 810G Hardware version 3.0

Discovery Timeline

• February 23, 2026 - CVE-2026-2980 published to NVD
• February 24, 2026 - Last updated in NVD database

Technical Details for CVE-2026-2980

Vulnerability Analysis

This buffer overflow vulnerability (CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer) stems from unsafe memory handling in the UTT HiPER 810G's web management interface. The vulnerable code path exists in the /goform/setSysAdm endpoint, which processes administrative password changes. When the passwd1 parameter is supplied with an oversized input, the strcpy function copies this data into a fixed-size buffer without performing bounds checking, resulting in adjacent memory being overwritten.

The network-accessible nature of this vulnerability significantly increases its risk profile, as attackers can target the device remotely. While the attack requires high privileges (authenticated administrative access), successful exploitation can lead to complete compromise of the device's confidentiality, integrity, and availability.

Root Cause

The root cause of this vulnerability is the use of the unsafe strcpy function without proper input length validation. The strcpy function does not perform bounds checking and will continue copying data until it encounters a null terminator, regardless of the destination buffer's size. When processing the passwd1 argument in the system administration form handler, the firmware fails to validate the input length before copying it to a stack or heap buffer, enabling classic buffer overflow exploitation.

Attack Vector

The attack is initiated remotely through the device's web management interface. An authenticated attacker with administrative privileges can craft a malicious HTTP POST request to the /goform/setSysAdm endpoint containing an oversized passwd1 parameter. The excessive input overflows the destination buffer, potentially overwriting return addresses, function pointers, or other critical memory structures. This can lead to arbitrary code execution with the privileges of the web server process, typically running as root on embedded devices.

The vulnerability mechanism involves sending an HTTP POST request to the /goform/setSysAdm endpoint with a passwd1 parameter containing more data than the allocated buffer can hold. The strcpy function blindly copies this data, corrupting adjacent memory regions. Attackers can leverage this to overwrite control flow data and redirect execution to attacker-controlled shellcode. Technical details and proof-of-concept information are available in the GitHub CVE Vulnerability Report.

Detection Methods for CVE-2026-2980

Indicators of Compromise

• Abnormally large HTTP POST requests to /goform/setSysAdm containing oversized passwd1 parameters
• Unexpected device reboots or crashes following administrative interface access
• Suspicious outbound network connections from the router to unknown external hosts
• Modified firmware or configuration files that differ from known-good baselines

Detection Strategies

• Monitor HTTP traffic to UTT HiPER 810G devices for POST requests to /goform/setSysAdm with passwd1 parameters exceeding expected length
• Implement network-based intrusion detection rules to flag potential buffer overflow payloads targeting embedded device web interfaces
• Deploy application-layer firewalls to inspect and block malformed requests to device management endpoints

Monitoring Recommendations

• Enable comprehensive logging on network devices and forward logs to a centralized SIEM for anomaly detection
• Establish baseline behavior for administrative interface access patterns and alert on deviations
• Regularly audit device configurations and firmware integrity using hash verification

How to Mitigate CVE-2026-2980

Immediate Actions Required

• Restrict network access to the UTT HiPER 810G web management interface using firewall rules and access control lists
• Disable remote administration if not required, limiting management to local console access only
• Implement network segmentation to isolate vulnerable devices from untrusted networks
• Monitor for exploitation attempts using network intrusion detection systems

Patch Information

No vendor patch information is currently available for this vulnerability. Organizations should monitor UTT's official channels for firmware updates addressing this buffer overflow. Additional technical details can be found in the VulDB CTI Report #347364 and the VulDB entry #347364.

Workarounds

• Implement strict access controls limiting administrative access to trusted IP addresses only
• Deploy a web application firewall (WAF) or reverse proxy to filter and sanitize inputs to the device's management interface
• Consider replacing affected devices with alternatives that receive regular security updates if no patch is forthcoming
• Use VPN-only access for device management to reduce the network attack surface

Network administrators should implement firewall rules to restrict access to the management interface. For example, limiting access to specific trusted management IP addresses and blocking external access to port 80/443 on affected devices can significantly reduce exploitation risk until a vendor patch becomes available.