CVE-2025-6734 in HiPER 840G
Summary
by MITRE • 06/27/2025
A vulnerability was found in UTT HiPER 840G up to 3.1.1-190328. It has been rated as critical. This issue affects the function sub_484E40 of the file /goform/formP2PLimitConfig of the component API. The manipulation of the argument except leads to buffer overflow. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
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Analysis
by VulDB Data Team • 07/01/2025
The vulnerability identified as CVE-2025-6734 represents a critical buffer overflow flaw in UTT HiPER 840G firmware versions up to 3.1.1-190328. This security weakness resides within the application programming interface component, specifically in the sub_484E40 function located in the /goform/formP2PLimitConfig file. The flaw manifests when the system processes input arguments, particularly the except parameter, which triggers unauthorized memory access patterns that can lead to arbitrary code execution. The vulnerability's classification as critical stems from its remote exploitability and the public disclosure of working exploit code, making it immediately dangerous to affected systems. The attack vector requires no authentication and can be initiated from external networks, presenting a significant threat to organizations relying on this network infrastructure equipment.
The technical implementation of this buffer overflow vulnerability demonstrates a classic programming error where insufficient bounds checking occurs when processing user-supplied input. The sub_484E40 function fails to validate the length of the except argument before copying it into a fixed-size buffer, allowing attackers to overwrite adjacent memory locations. This type of vulnerability maps directly to CWE-121, which describes stack-based buffer overflow conditions, and also aligns with CWE-787, describing out-of-bounds write vulnerabilities. The attack can be executed through the web-based API interface, leveraging the device's HTTP server functionality to deliver malicious payloads. The exploitability is further enhanced by the fact that the vulnerability exists in a core configuration management function, providing attackers with potential access to critical network settings and system resources. This flaw operates at the application layer and can be classified under ATT&CK technique T1210 for exploiting known vulnerabilities, with potential lateral movement capabilities through compromised network infrastructure.
The operational impact of this vulnerability extends beyond simple system compromise, as it affects network infrastructure devices that serve as critical points of control and monitoring within enterprise environments. Organizations utilizing UTT HiPER 840G devices face risks including complete system takeover, persistent backdoor access, data exfiltration, and disruption of network services. The remote exploitability means that attackers can target these devices from anywhere on the internet without requiring physical access or network proximity. The lack of vendor response to early disclosure attempts compounds the risk, leaving affected organizations without official patches or mitigation guidance during the active exploitation period. Network administrators may experience unauthorized access to P2P traffic limiting configurations, potentially allowing attackers to bypass security controls and establish persistent access points within the network. The vulnerability's presence in a configuration management API also raises concerns about privilege escalation and potential access to sensitive network parameters that could be leveraged for broader attacks.
Organizations must implement immediate mitigations while awaiting official patches from the vendor, which unfortunately have not been provided despite early disclosure efforts. Network segmentation should be implemented to isolate affected devices from critical network segments, while firewall rules should be configured to restrict access to the device's web interface and API endpoints. Regular monitoring of network traffic for unusual patterns and potential exploitation attempts is essential, particularly focusing on traffic to the affected API endpoints. The implementation of intrusion detection systems with signatures for known exploit patterns related to buffer overflow vulnerabilities can provide early warning capabilities. Additionally, organizations should consider disabling unnecessary API functions and implementing authentication controls where possible, though the vulnerability's design suggests that even authenticated access may not prevent exploitation. The lack of vendor response necessitates proactive threat hunting activities and consideration of alternative network infrastructure solutions until official remediation is available. Security teams should also prepare incident response procedures specifically addressing potential compromise of network infrastructure devices, as the impact of such compromises can be far-reaching and difficult to contain.