CVE-2026-4862 is a buffer overflow vulnerability identified in the UTT HiPER 1250GW network device firmware versions up to 3.2.7-210907-180535. The vulnerability arises from unsafe use of the strcpy function in the Parameter Handler component, specifically in the /goform/formConfigDnsFilterGlobal endpoint that processes the GroupName parameter. Because strcpy does not perform bounds checking, an attacker can supply an overly long GroupName argument, causing a buffer overflow. This overflow can overwrite adjacent memory, potentially allowing remote attackers to execute arbitrary code or cause a denial of service. The vulnerability is remotely exploitable without requiring authentication or user interaction, increasing its severity and ease of exploitation. The CVSS v4.0 base score is 8.7 (high), reflecting the network attack vector, low attack complexity, no privileges or user interaction needed, and high impact on confidentiality, integrity, and availability. Although no active exploits have been reported in the wild, the public disclosure of exploit details raises the likelihood of future exploitation. The affected component is critical for DNS filtering configuration, making the device a high-value target for attackers aiming to disrupt or control network traffic. No official patches have been linked yet, so mitigation may require workarounds or device replacement until updates are available.

The impact of CVE-2026-4862 is significant for organizations deploying UTT HiPER 1250GW devices, which are typically used for DNS filtering and network security. Successful exploitation can lead to remote code execution, allowing attackers to take full control of the device, manipulate DNS filtering rules, intercept or redirect network traffic, or cause denial of service. This compromises the confidentiality, integrity, and availability of network communications and can serve as a foothold for further lateral movement within the network. Organizations relying on these devices for perimeter defense or internal segmentation may face increased risk of data breaches, service outages, or malware propagation. The lack of required authentication and user interaction lowers the barrier for attackers, making automated mass scanning and exploitation feasible. The public availability of exploit code further elevates the threat level. Critical infrastructure, enterprises, and service providers using this device are at risk of operational disruption and reputational damage if the vulnerability is exploited.

To mitigate CVE-2026-4862, organizations should immediately assess their inventory for affected UTT HiPER 1250GW devices running firmware up to version 3.2.7-210907-180535. Since no official patches are currently linked, the following steps are recommended: 1) Restrict network access to the device management interfaces, especially the /goform/formConfigDnsFilterGlobal endpoint, by implementing strict firewall rules and network segmentation to limit exposure to trusted administrators only. 2) Monitor network traffic and device logs for unusual or malformed requests targeting the vulnerable endpoint to detect potential exploitation attempts. 3) Disable or restrict remote management features if not essential, reducing the attack surface. 4) Engage with the vendor for firmware updates or security advisories and apply patches promptly once available. 5) Consider deploying intrusion prevention systems (IPS) with signatures targeting this vulnerability to block exploit attempts. 6) As a longer-term measure, evaluate alternative devices or solutions with better security track records if patching is delayed. 7) Conduct regular security audits and penetration testing to verify the effectiveness of mitigations and detect any compromise early.