What is the CVSS score of EUVD-2026-40865?

EUVD-2026-40865 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:N/I:N/A:H. EPSS exploitation probability: 0.2%.

Which versions of UTT nv518G are affected by EUVD-2026-40865?

UTT nv518G gateway/router firmware contains an unauthenticated denial-of-service vulnerability (CVSS 7.5) that allows remote attackers to crash the device, disrupting network availability.

How to fix or mitigate EUVD-2026-40865?

Within 24 hours: Inventory all UTT nv518G devices in production; disable or restrict access to the gohead web-service handler if feasible without operational impact. Within 7 days: Deploy firewall rules to restrict network access to affected devices to authorized administration networks only; implement rate-limiting on web-service ports (typically 80/443). Within 30 days: Engage UTT regarding patch timeline; evaluate and procure replacement gateway/router firmware versions or alternative vendors; plan staged migration.

UTT nv518G EUVD-2026-40865

| CVE-2026-52195 HIGH

Classic Buffer Overflow (CWE-120)

2026-06-30 mitre

GHSA-p6vq-whcp-3j3j

Buffer Overflow Denial Of Service N A

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:N/I:N/A:H

vuln.today AI

7.5 HIGH

Unauthenticated network-reachable web handler triggered by a single crafted request (AV:N/AC:L/PR:N/UI:N); impact is a crash only, so C:N/I:N and A: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

None

Integrity

None

Availability

High

Lifecycle Timeline

Analysis Generated

Jul 01, 2026 - 16:25 vuln.today

CVSS changed

Jul 01, 2026 - 16:22 NVD

7.5 (HIGH)

CVE Published

Jun 30, 2026 - 00:00 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_472f08 component

AnalysisAI

Denial of service in the UTT nv518G gateway/router (firmware nv518GV3 v3.2.7-210919-161313) allows a remote, unauthenticated attacker to crash the device by triggering a buffer overflow in the gohead web-service handler at function sub_472f08 (FUN_00472f08). The CVSS 3.1 score of 7.5 reflects availability-only impact (A:H, C:N/I:N) over the network with no privileges or user interaction. EPSS is low (0.22%, 13th percentile) and the CVE is not in CISA KEV; a third-party technical write-up exists on GitHub, but no active exploitation is confirmed.

Technical ContextAI

The affected component is 'gohead', which is the embedded web server (a GoAhead-style HTTP daemon common on SOHO networking appliances) running on UTT's nv518G firmware; sub_472f08 / FUN_00472f08 is a decompiler-derived address for the request-handling routine that mishandles input length. The root cause is CWE-120 (Buffer Copy without Checking Size of Input, 'Classic Buffer Overflow'): attacker-controlled data is copied into a fixed-size stack or global buffer without bounds validation, corrupting adjacent memory and crashing the process. The CPE data is uninformative ('cpe:2.3:a:n/a:n/a') and does not identify the product, so affected-scope identification relies on the description and the vendor firmware string rather than a normalized CPE.

RemediationAI

No vendor-released patched firmware version is identified in the available data, so no exact fix version can be cited; check UTT's download center (https://utt.com.cn/downloadcenter.php?filetypeid=3&model=518G&lang=zhcn) for an updated 518G firmware image and apply it once released. As compensating controls, restrict access to the device's web management interface - do not expose the gohead HTTP/HTTPS management port to the internet or untrusted VLANs, and place management behind an ACL or VPN so only trusted admin hosts can reach it (trade-off: remote administration convenience is lost). Where feasible, front the device with an upstream firewall/IPS rule that rate-limits or drops malformed oversized requests to the management endpoint, and monitor for unexpected device reboots as an exploitation indicator. Because the flaw is a crash rather than code execution, an automatic-restart/watchdog policy limits outage duration but does not prevent the DoS.