CVE-2026-52196: UTT nv518G Buffer Overflow Denial-of-Service Vulnerability

Technical summary

CVE-2026-52196 is a classic buffer overflow (CWE-120) in the gohead/sub_416f28 component of UTT nv518G. The vulnerability is network-accessible, requires no authentication or user interaction, and triggers a denial-of-service condition when memory bounds are exceeded. The CVSS 3.1 score of 7.5 reflects the high impact on availability, zero impact on confidentiality and integrity, and the ease of exploitation from the network boundary.

Business impact

Organizations running affected UTT nv518G devices face service disruption risk. Unlike vulnerabilities that lead to data theft or system compromise, this threat manifests as availability loss—devices become unresponsive and require manual restart or intervention. In environments where these devices support critical functions (monitoring, gateway, or access control), DoS could impact productivity or operational continuity.

Affected systems

The vulnerability affects UTT nv518G devices running firmware version nv518GV3v3.2.7-210919-161313. Confirm your device model and firmware version through the device's administration interface or system information page. No vendor product data is currently available in structured vulnerability feeds, so verify your environment against the vendor's advisory and security bulletins.

Exploitability

This vulnerability carries high exploitability. The attack vector is network-based, no credentials are required, no special user interaction is needed, and the attack complexity is low. Any attacker with network access to the device can trigger the denial-of-service condition. However, the vulnerability is not yet listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, so active exploitation in the wild has not been formally documented to date.

Remediation

Firmware updates from UTT addressing this buffer overflow should be prioritized. Contact UTT directly or check their security advisory portal for patches released after the vulnerability publication date (June 30, 2026). In the interim, isolate or restrict network access to affected nv518G devices using firewall rules, ACLs, or network segmentation to limit exposure to untrusted networks.

Patch guidance

Obtain the latest firmware release for UTT nv518G from the vendor's support portal or security advisory page. Verify that the firmware version number is higher than nv518GV3v3.2.7-210919-161313. Test the patch in a non-production environment first to ensure compatibility with your deployment. Once validated, schedule a maintenance window to apply the update, as device restart may be required. Confirm successful patch application by checking the firmware version post-update.

Detection guidance

Monitor network traffic to affected nv518G devices for abnormal or malformed input patterns targeting the gohead component. Implement intrusion detection system (IDS) signatures that detect buffer overflow attempts against this device class. Review device logs for unexpected restarts, crashes, or 'denial-of-service' error conditions. Tools like network packet analyzers (tcpdump, Wireshark) can help capture and inspect suspicious requests if incident investigation is needed.

Why prioritize this

Despite the availability-only impact, the high CVSS score (7.5) reflects unauthenticated network access and ease of exploitation. Organizations with business-critical applications or services relying on these devices should prioritize patching. Conversely, if nv518G devices serve non-critical functions or are already isolated from untrusted networks, remediation can be scheduled in a standard maintenance cycle. The absence of KEV designation means active exploitation has not been observed at scale, reducing urgency slightly.

Risk score, explained

The 7.5 CVSS 3.1 score captures a denial-of-service vulnerability with network-based attack surface and low attack complexity. The high severity reflects maximum availability impact (A:H) but zero confidentiality and integrity impact (C:N, I:N). The unauthenticated, no-user-interaction nature (PR:N, UI:N) elevates the score; however, the impact is limited to availability, preventing a critical or 9.0+ rating.

Frequently asked questions