CVE-2026-52193: UTT nv518G Buffer Overflow RCE Vulnerability

Technical summary

CVE-2026-52193 is a classic buffer overflow (CWE-120) discovered in the gohead/sub_447CAC component of UTT nv518G network equipment. The flaw allows a remote, unauthenticated attacker to overflow a buffer by sending malicious input, leading to denial of service through crash or resource exhaustion. The attack vector is network-based with low complexity, meaning an attacker needs only network access and can exploit the vulnerability with a single request. The CVSS 3.1 score of 7.5 (HIGH) reflects the high confidentiality impact alongside availability degradation, though integrity remains unaffected.

Business impact

Denial of service attacks against network infrastructure can disrupt operations, interrupt communications, and degrade service availability for dependent systems. Organizations relying on UTT nv518G devices for network functions face potential downtime if the vulnerability is exploited. The lack of authentication requirements means the threat surface is broad—any remote attacker with network access could attempt exploitation without credentials or special privileges.

Affected systems

UTT nv518G and nv518GV3 devices are affected, specifically those running firmware version nv518GV3v3.2.7-210919-161313 or earlier builds. The vulnerability resides in the gohead web server component. Organizations should audit their device inventory to identify affected hardware and firmware versions in production environments.

Exploitability

The vulnerability has moderate to high exploitability characteristics. Network accessibility (no special network configuration required), low attack complexity, and lack of authentication or user interaction requirements all lower the bar for attack execution. While no public exploit or active KEV listing is currently documented, the straightforward nature of buffer overflow attacks means exploitation proof-of-concept code could emerge relatively quickly. Security teams should treat this as actively exploitable.

Remediation

Immediate action should focus on identifying all UTT nv518G devices running the affected firmware. Coordinate with UTT for availability of patched firmware versions that address the buffer overflow in the gohead component. Pending patch deployment, consider isolating affected devices on network segments with restricted external access, implementing network-based controls to limit connections to these devices, and monitoring for anomalous traffic patterns targeting the gohead service.

Patch guidance

Contact UTT directly to obtain a patched firmware image for the nv518G and nv518GV3 device lines. Verify the firmware version number against the vendor advisory to confirm you are deploying a version that remediates CWE-120 in the gohead component. Test the patched firmware in a non-production environment first to validate functionality and compatibility before rolling out to production devices. Follow UTT's documented firmware upgrade procedures to minimize service disruption.

Detection guidance

Monitor network traffic for unusual requests directed at UTT nv518G devices, particularly payloads that attempt to overflow buffers or contain excessively long input strings. Implement intrusion detection signatures that look for buffer overflow attack patterns targeting the gohead service. Review device logs for unexpected crashes, restarts, or error conditions coinciding with external traffic spikes. Baseline normal gohead service behavior and alert on deviations such as high CPU usage or memory exhaustion tied to the vulnerable component.

Why prioritize this

This vulnerability warrants high priority remediation due to the combination of high CVSS score (7.5), network accessibility without authentication, and the critical role network infrastructure plays in business continuity. The denial of service impact directly threatens availability. Although not yet listed in CISA's KEV catalog, the straightforward exploitation path and lack of complexity mean it should be treated as imminent risk. Remediation should be scheduled within 1–2 weeks depending on your device count and operational constraints.

Risk score, explained

The CVSS 3.1 score of 7.5 reflects a HIGH severity rating driven by high confidentiality impact and the ease of remote exploitation. The vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N indicates network attack vector, low complexity, no privileges or user interaction required, and unchanged scope. Although the integrity impact is none, the high confidentiality impact and network-accessible nature of the vulnerability elevate the overall risk. Practical impact on your organization may vary based on device exposure and network segmentation.

Frequently asked questions