CVE-2026-2135: UTT HiPER 810 RCE Vulnerability

CVE-2026-2135 Overview

A command injection vulnerability has been identified in UTT HiPER 810 router firmware version 1.7.4-141218. The vulnerability exists in the function sub_43F020 of the file /goform/formPdbUpConfig, where manipulation of the policyNames argument allows for arbitrary command injection. This vulnerability can be exploited remotely by authenticated attackers, enabling them to execute malicious commands on the affected device.

Critical Impact

Remote authenticated attackers can inject arbitrary commands through the policyNames parameter, potentially leading to complete device compromise, unauthorized configuration changes, or using the device as a pivot point for further network attacks.

Affected Products

• UTT HiPER 810 firmware version 1.7.4-141218

Discovery Timeline

• 2026-02-08 - CVE-2026-2135 published to NVD
• 2026-02-09 - Last updated in NVD database

Technical Details for CVE-2026-2135

Vulnerability Analysis

This command injection vulnerability (CWE-74) affects the UTT HiPER 810 router's web management interface. The vulnerable function sub_43F020 processes user-supplied input from the policyNames parameter without adequate sanitization or validation. When a user submits a request to the /goform/formPdbUpConfig endpoint, the application fails to properly neutralize special elements that could be interpreted as commands by the underlying operating system.

The vulnerability requires network access and low-privilege authentication to exploit. While the individual impact on confidentiality, integrity, and availability is limited, the ability to execute arbitrary commands remotely makes this a significant security concern for affected devices. The exploit has been made public, increasing the risk of widespread exploitation.

Root Cause

The root cause of this vulnerability is improper input validation (CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component). The sub_43F020 function accepts the policyNames argument and passes it to system command execution functions without properly sanitizing or escaping special characters. This allows attackers to inject shell metacharacters and arbitrary commands that are then executed with the privileges of the web server process.

Attack Vector

The attack vector is network-based, requiring the attacker to have authenticated access to the UTT HiPER 810 router's web management interface. The attacker can craft a malicious HTTP request to the /goform/formPdbUpConfig endpoint with a specially crafted policyNames parameter containing shell commands. These commands are then executed by the router's operating system, potentially allowing the attacker to:

• Execute arbitrary system commands
• Read or modify router configuration files
• Establish persistent backdoor access
• Pivot to attack other devices on the network
• Disrupt router operations causing denial of service

The vulnerability is exploited by injecting command separators (such as ;, |, or &&) followed by malicious commands into the policyNames parameter. Technical details regarding the exploitation methodology can be found in the GitHub CVE Readme Document.

Detection Methods for CVE-2026-2135

Indicators of Compromise

• Unusual HTTP POST requests to /goform/formPdbUpConfig containing shell metacharacters in the policyNames parameter
• Unexpected system processes spawned by the router's web server process
• Anomalous outbound network connections from the router to unknown IP addresses
• Modified configuration files or unauthorized user accounts on the device

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block requests containing shell metacharacters in form parameters
• Monitor HTTP traffic to the router's management interface for suspicious patterns in the policyNames parameter
• Deploy intrusion detection system (IDS) signatures to identify command injection attempts targeting UTT HiPER devices
• Enable and review router access logs for unusual authentication patterns or repeated form submissions

Monitoring Recommendations

• Configure alerts for any access to the /goform/formPdbUpConfig endpoint from untrusted networks
• Monitor CPU and memory utilization on affected devices for anomalies indicating malicious command execution
• Review authentication logs regularly for unauthorized access attempts to the management interface
• Implement network segmentation monitoring to detect lateral movement attempts originating from compromised routers

How to Mitigate CVE-2026-2135

Immediate Actions Required

• Restrict access to the UTT HiPER 810 web management interface to trusted networks only using firewall rules
• Disable remote management access if not required for operations
• Implement strong authentication credentials and review existing user accounts
• Monitor the device for signs of compromise and suspicious activity

Patch Information

At the time of publication, no vendor patch has been officially released for this vulnerability. Organizations should monitor UTT's official channels for firmware updates that address this command injection issue. Additional technical information and vulnerability details are available through VulDB #344770.

Workarounds

• Implement network-level access controls to restrict management interface access to specific trusted IP addresses
• Deploy a reverse proxy with input validation in front of the router's web interface to filter malicious requests
• Consider replacing affected devices with alternatives that do not contain this vulnerability if no patch becomes available
• Use VPN connections for all remote management activities to add an additional layer of authentication

# Configuration example - Firewall rule to restrict management access
# Allow management access only from trusted admin network
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP

# Block external access to the vulnerable endpoint
iptables -A INPUT -p tcp --dport 80 -m string --string "/goform/formPdbUpConfig" --algo bm -j DROP