What is the CVSS score of EUVD-2026-40864?

EUVD-2026-40864 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. EPSS exploitation probability: 0.2%.

Which versions of UTT nv518G are affected by EUVD-2026-40864?

UTT nv518G gateway/router devices are vulnerable to remote denial-of-service attacks that can crash the network appliance, disrupting organizational connectivity and business operations.

How to fix or mitigate EUVD-2026-40864?

Within 24 hours: Conduct complete asset inventory of all UTT nv518G gateway/router devices; verify affected firmware versions (nv518GV3v3.2.7-210919-161313 and earlier); document network placement and criticality. Within 7 days: Implement firewall rules and network access controls to restrict unauthenticated remote access to the gohead web-server interface; consider isolating affected devices to internal management networks only. Within 30 days: Contact UTT for patch or end-of-life guidance; develop device replacement or upgrade strategy; establish monitoring and alerting for abnormal device restarts.

UTT nv518G EUVD-2026-40864

| CVE-2026-52193 HIGH

Classic Buffer Overflow (CWE-120)

2026-06-30 cve@mitre.org

GHSA-wj3w-v66w-x298

Buffer Overflow Denial Of Service

7.5

CVSS 3.1 · Vendor: mitre

Severity by source

Vendor (mitre) PRIMARY

7.5 HIGH

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

vuln.today AI

7.5 HIGH

Remote, unauthenticated, no interaction against the exposed web service (AV:N/AC:L/PR:N/UI:N); impact is a crash/DoS so A:H with C:N/I:N, correcting the input vector's C:H.

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Primary rating from Vendor (mitre).

CVSS VectorVendor: mitre

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Lifecycle Timeline

Analysis Generated

Jul 01, 2026 - 21:32 vuln.today

CVSS changed

Jul 01, 2026 - 19:22 NVD

7.5 (None) 7.5 (HIGH)

CVE Published

Jun 30, 2026 - 23:17 cve.org

UNKNOWN (no severity yet)

DescriptionCVE.org

Buffer Overflow vulnerability in UTT nv518G nv518GV3v3.2.7-210919-161313 allows a remote attacker to cause a denial of service via the gohead/sub_447CAC component

AnalysisAI

Denial of service in the UTT nv518G gateway/router (firmware nv518GV3v3.2.7-210919-161313) allows a remote attacker to crash the device by triggering a buffer overflow in the gohead/sub_447CAC web-server routine. Publicly available exploit code exists (referenced GitHub CVEreport analysis) but it is not listed in CISA KEV; EPSS is low at 0.22% (13th percentile), indicating no observed widespread exploitation. Note a data conflict: the description and tags describe a DoS, yet the supplied CVSS vector encodes a confidentiality impact (C:H/A:N) rather than availability.

Technical ContextAI

The affected component 'gohead' points to the embedded GoAhead/goahead-style HTTP server that ships on UTT's nv-series enterprise routers/VPN gateways, and sub_447CAC/FUN_00447048 is a disassembler-derived label for the vulnerable handler function reverse-engineered from the firmware binary. The root cause is CWE-120 (Classic Buffer Overflow / copy without checking input size), meaning attacker-supplied data reaching this handler is written into a fixed-size stack or heap buffer without bounds validation, corrupting adjacent memory and crashing the web service or device. Because the flaw lives in the management/web interface parser, it is reachable over the network wherever that interface is exposed.

RemediationAI

No vendor-released patch version is identified in the available data, so the primary action is to check the UTT download center (https://utt.com.cn/downloadcenter.php?filetypeid=3&model=518G&lang=zhcn) for a firmware build newer than v3.2.7-210919-161313 and apply it once published. As compensating controls until a fix exists: restrict access to the device web/management interface (the gohead HTTP service) so it is not reachable from the WAN or untrusted networks - bind management to a dedicated LAN/VLAN or management IP allowlist, which prevents remote triggering at the cost of requiring on-network access for administration; block inbound access to the management HTTP port at the perimeter firewall, with the side effect of disabling any legitimate remote administration; and monitor the device for unexpected reboots or web-service crashes as a detection fallback. Because the flaw is a crash rather than code execution per the description, the practical goal is limiting network reachability of the vulnerable endpoint.