CVE-2026-1139 identifies a critical buffer overflow vulnerability in the UTT 进取 520W device, version 1.7.7-180627. The vulnerability resides in the strcpy function call within the /goform/ConfigExceptMSN endpoint, which improperly handles input data, allowing an attacker to overflow the buffer. This flaw can be exploited remotely over the network without requiring authentication or user interaction, making it highly accessible for attackers. The buffer overflow can lead to arbitrary code execution or cause the device to crash, resulting in denial of service. The vulnerability has been publicly disclosed, and although no known exploits are currently observed in the wild, the availability of public exploit code increases the risk of imminent attacks. The vendor was contacted but has not responded or issued a patch, leaving users exposed. The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H) indicates network attack vector, low complexity, no attack or user interaction required, and high impact on confidentiality, integrity, and availability. This vulnerability is particularly concerning for organizations relying on UTT 进取 520W devices for network operations, as exploitation could compromise critical infrastructure components.

For European organizations, the impact of CVE-2026-1139 can be severe. The vulnerability allows remote attackers to execute arbitrary code or cause denial of service on affected devices, potentially disrupting network services or enabling further lateral movement within corporate networks. This can lead to data breaches, operational downtime, and compromise of sensitive information. Critical infrastructure sectors such as telecommunications, manufacturing, and government agencies using UTT 进取 520W devices may face significant operational risks. The lack of vendor response and patch availability increases exposure time, raising the likelihood of exploitation. Additionally, the vulnerability's ease of exploitation without authentication means attackers can target these devices en masse, potentially affecting supply chains and service providers across Europe.

1. Immediately isolate UTT 进取 520W devices from untrusted networks to reduce exposure. 2. Implement strict network segmentation and firewall rules to limit access to the /goform/ConfigExceptMSN endpoint. 3. Monitor network traffic for unusual requests or attempts to access the vulnerable endpoint. 4. Disable or restrict remote management interfaces if possible until a patch is available. 5. Employ intrusion detection/prevention systems (IDS/IPS) with signatures targeting known exploit patterns for this vulnerability. 6. Engage with UTT or authorized vendors for any unofficial patches or mitigations. 7. Plan for device replacement or firmware upgrade once a secure version is released. 8. Conduct regular security audits and vulnerability scans focusing on network devices to identify and remediate similar issues proactively.