CVE-2026-2846: UTT HiPER 520 Firmware RCE Vulnerability

CVE-2026-2846 Overview

A critical OS command injection vulnerability has been identified in the UTT HiPER 520 router firmware version 1.7.7-160105. This vulnerability affects the sub_44D264 function within the /goform/formPdbUpConfig endpoint of the Web Management Interface. Attackers can exploit this flaw by manipulating the policyNames argument, allowing them to execute arbitrary operating system commands remotely.

Critical Impact
Remote attackers with administrative access can achieve complete system compromise through OS command injection, potentially leading to unauthorized device control, network infiltration, and data exfiltration.

Affected Products

UTT HiPER 520 Firmware version 1.7.7-160105
UTT 520 Hardware version 3.0
UTT 520 Web Management Interface

Discovery Timeline

2026-02-20 - CVE-2026-2846 published to NVD
2026-02-24 - Last updated in NVD database

Technical Details for CVE-2026-2846

Vulnerability Analysis

This vulnerability represents a classic OS command injection flaw (CWE-77) in an embedded network device. The web management interface fails to properly sanitize user-supplied input in the policyNames parameter before passing it to system-level command execution functions. When an authenticated administrator sends a malicious request to the vulnerable endpoint, the unsanitized input is concatenated directly into a system command string, allowing arbitrary command execution with the privileges of the web server process—typically root on embedded devices.

The exploitation requires network access to the device's management interface and valid administrative credentials. However, given that many network devices retain default credentials or have weak password policies, this barrier may be lower than expected in real-world deployments. The publicly disclosed nature of this exploit increases the risk of opportunistic attacks against exposed devices.

Root Cause

The root cause of this vulnerability lies in improper input validation within the sub_44D264 function. The policyNames argument is accepted from user input and incorporated into operating system commands without adequate sanitization or escaping. This allows shell metacharacters and command separators to be interpreted by the underlying shell, enabling command injection attacks.

Attack Vector

The attack is executed remotely via the network against the web management interface. An attacker must have authenticated access to the administrative interface to reach the vulnerable /goform/formPdbUpConfig endpoint. Once authenticated, the attacker crafts a malicious HTTP request containing shell commands embedded within the policyNames parameter.

The vulnerability allows attackers to inject commands that will be executed on the underlying operating system. This could enable activities such as:

Establishing reverse shells for persistent remote access
Modifying device configurations to intercept or redirect network traffic
Extracting sensitive configuration data including credentials
Using the compromised device as a pivot point for lateral movement within the network

For technical details on the exploitation methodology, refer to the GitHub UTT520CVE Documentation.

Detection Methods for CVE-2026-2846

Indicators of Compromise

Unusual HTTP POST requests to /goform/formPdbUpConfig containing shell metacharacters in parameters
Unexpected outbound connections from the router to external IP addresses
Anomalous process execution on the device not consistent with normal operation
Modifications to device configuration files or startup scripts

Detection Strategies

Monitor web server access logs for requests to /goform/formPdbUpConfig with suspicious parameter values
Implement network-based intrusion detection rules to identify command injection patterns in HTTP traffic
Deploy application-layer firewalls capable of inspecting and blocking malicious payloads targeting this endpoint
Conduct periodic configuration audits to detect unauthorized changes

Monitoring Recommendations

Enable verbose logging on the UTT HiPER 520 device if supported
Implement SIEM correlation rules to detect multiple failed authentication attempts followed by successful access to sensitive endpoints
Monitor for DNS queries or network connections to known malicious infrastructure from network device IP addresses

How to Mitigate CVE-2026-2846

Immediate Actions Required

Restrict access to the web management interface to trusted networks only using firewall rules or network segmentation
Ensure strong, unique administrative credentials are configured on the device
Disable remote management access from untrusted networks, particularly from the internet
Review access logs for evidence of prior exploitation attempts

Patch Information

At the time of publication, no official vendor patch has been announced for this vulnerability. Users should monitor UTT's official channels for firmware updates. Additional technical information is available through VulDB #347082 and VulDB CTI ID #347082.

Workarounds

Implement network-level access controls to restrict management interface access to authorized IP addresses only
Consider placing the device behind a VPN to prevent direct exposure of the management interface
If the device is end-of-life or no patch is forthcoming, evaluate replacement with a supported alternative
Deploy an intrusion prevention system (IPS) with custom rules to block exploitation attempts targeting this endpoint

bash

# Example iptables rule to restrict management interface access
# Replace 192.168.1.0/24 with your 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
iptables -A INPUT -p tcp --dport 443 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP