CVE-2026-1138 is a buffer overflow vulnerability identified in the UTT 进取 520W device, firmware version 1.7.7-180627. The flaw exists in the strcpy function used in the /goform/ConfigExceptQQ endpoint, which does not properly validate input length, allowing an attacker to overflow the buffer by sending crafted data. This vulnerability can be exploited remotely over the network without requiring authentication or user interaction, making it highly accessible to attackers. Successful exploitation could lead to arbitrary code execution, enabling attackers to take control of the device, or cause denial of service by crashing the system. The vulnerability was responsibly disclosed to the vendor, but no response or patch has been issued, and the exploit code has been published publicly, increasing the likelihood of exploitation. The CVSS 4.0 score is 8.7 (high), reflecting the ease of exploitation and the severe impact on confidentiality, integrity, and availability. The device is likely used in telecommunications or networking environments, where compromise could have cascading effects on connected systems and services.

For European organizations, the impact of this vulnerability could be significant, especially for those relying on UTT 进取 520W devices in their network infrastructure. Exploitation could lead to unauthorized control over network devices, resulting in data breaches, interception or manipulation of communications, and disruption of services. Critical sectors such as telecommunications, government networks, and industrial control systems could face operational outages or espionage risks. The lack of vendor response and patches increases exposure time, making proactive defense essential. Additionally, the public availability of exploit code lowers the barrier for attackers, including cybercriminals and nation-state actors, to target vulnerable systems. This could lead to widespread attacks affecting confidentiality, integrity, and availability of network services across Europe.

Given the absence of vendor patches, European organizations should implement layered defenses. First, restrict network access to the vulnerable device’s management interfaces, ideally isolating them in secure network segments or behind firewalls with strict access control lists. Deploy intrusion detection and prevention systems (IDS/IPS) configured to detect buffer overflow attempts targeting the /goform/ConfigExceptQQ endpoint. Employ network-level anomaly detection to identify unusual traffic patterns. Regularly audit and inventory network devices to identify any UTT 进取 520W devices running the affected firmware version. Where possible, replace or upgrade devices to models from vendors with active security support. Additionally, implement strict input validation and filtering at network gateways to block malformed packets. Monitor device logs for signs of exploitation attempts and establish incident response plans tailored to network device compromise scenarios.