CVE-2026-3700 in HiPER 810G
Summary
by MITRE • 03/08/2026
A weakness has been identified in UTT HiPER 810G up to 1.7.7-171114. Affected is the function strcpy of the file /goform/formConfigDnsFilterGlobal. This manipulation causes buffer overflow. Remote exploitation of the attack is possible. The exploit has been made available to the public and could be used for attacks.
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Analysis
by VulDB Data Team • 03/12/2026
The vulnerability CVE-2026-3700 represents a critical buffer overflow flaw in UTT HiPER 810G firmware versions up to 1.7.7-171114. This weakness resides within the strcpy function implementation in the /goform/formConfigDnsFilterGlobal file, creating a dangerous condition that allows attackers to overwrite adjacent memory locations. The affected device operates as a network security appliance that handles DNS filtering configurations, making this vulnerability particularly concerning for organizations relying on network traffic monitoring and control. The buffer overflow occurs when the system processes user-supplied input without proper bounds checking, enabling malicious actors to inject arbitrary code into the device's memory space. This particular implementation flaw demonstrates poor input validation practices that directly violates established security principles for secure coding.
The technical exploitation of this vulnerability follows a well-documented pattern that aligns with CWE-121, which describes buffer overflow conditions where insufficient bounds checking allows data to overwrite adjacent memory regions. Attackers can remotely manipulate the DNS filtering configuration interface to trigger the buffer overflow by sending specially crafted input parameters through the web form interface. The strcpy function's lack of size validation means that input data exceeding the allocated buffer space will overwrite adjacent memory, potentially allowing attackers to overwrite return addresses, function pointers, or other critical control data. This remote code execution capability enables threat actors to gain full administrative control over the device, potentially compromising the entire network infrastructure that relies on this DNS filtering appliance for traffic management and security enforcement.
The operational impact of CVE-2026-3700 extends beyond simple device compromise, creating significant risks for enterprise network security. Organizations utilizing UTT HiPER 810G devices for DNS filtering and content control face potential exposure to man-in-the-middle attacks, data exfiltration, and network reconnaissance activities. The vulnerability's public exploit availability means that threat actors can readily weaponize this weakness without requiring specialized knowledge or resources. Network administrators may experience unauthorized access to sensitive configuration data, enabling attackers to modify DNS filtering rules to redirect traffic to malicious domains or disable security features entirely. The attack surface expands significantly when considering that DNS filtering appliances often serve as central points of network control, making this vulnerability particularly dangerous for organizations with limited network segmentation or monitoring capabilities.
Mitigation strategies for CVE-2026-3700 should prioritize immediate firmware updates from UTT to address the identified buffer overflow condition. Organizations must implement network segmentation to isolate affected devices from critical infrastructure and establish monitoring protocols to detect anomalous traffic patterns or unauthorized configuration changes. Security teams should deploy network intrusion detection systems capable of identifying exploitation attempts targeting the specific formConfigDnsFilterGlobal endpoint. The implementation of web application firewalls and input validation controls can provide additional defense layers, though these measures are secondary to the primary requirement of firmware patching. According to ATT&CK framework technique T1059.007 for command and script interpreter, attackers leveraging this vulnerability could execute commands through the compromised device, making proper access controls and network monitoring essential defensive measures. Organizations should also conduct comprehensive vulnerability assessments to identify other potential buffer overflow conditions in similar network security appliances and establish incident response procedures specifically addressing remote code execution vulnerabilities in network infrastructure devices.