How severe is CVE-2026-4861?

CVE-2026-4861 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-4861 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-4861?

CVE-2026-4861 affects Wavlink Wl-nu516u1 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-4861?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-4861 have an EU (EUVD) identifier?

Yes. CVE-2026-4861 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16146.

When was CVE-2026-4861 published?

CVE-2026-4861 was published on 2026-03-26 and last updated on 2026-06-17.

CVE-2026-4861

CVE-2026-4861 is a high-severity vulnerability in Wavlink Wl-nu516u1 Firmware with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-119.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
CVSS v4: 7.4
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-16146
Weakness: CWE-119
Affected product: Wavlink Wl-nu516u1 Firmware
Published: 2026-03-26
Last modified: 2026-06-17

Description

A weakness has been identified in Wavlink WL-NU516U1 260227. This vulnerability affects the function ftext of the file /cgi-bin/nas.cgi. This manipulation of the argument Content-Length causes stack-based buffer overflow. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.

Frequently asked questions

What is CVE-2026-4861?: A weakness has been identified in Wavlink WL-NU516U1 260227. This vulnerability affects the function ftext of the file /cgi-bin/nas.cgi. This manipulation of the argument Content-Length causes stack-based buffer overflow. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.
How severe is CVE-2026-4861?: CVE-2026-4861 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-4861 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-4861?: CVE-2026-4861 affects Wavlink Wl-nu516u1 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-4861?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-4861 have an EU (EUVD) identifier?: Yes. CVE-2026-4861 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16146.
When was CVE-2026-4861 published?: CVE-2026-4861 was published on 2026-03-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:wavlink:wl-nu516u1_firmware:m16u1_v260227:*:*:*:*:*:*:*

More vulnerabilities in Wavlink Wl-nu516u1 Firmware

CVE-2026-3703 — Critical (CVSS 9.8): A flaw has been found in Wavlink NU516U1 251208. This affects the function sub_401A10 of the file /cgi-bin/login.cgi.…
CVE-2026-3613 — High (CVSS 7.2): A vulnerability was identified in Wavlink WL-NU516U1 V240425. This vulnerability affects the function sub_401A0C of the…
CVE-2026-3612 — High (CVSS 7.2): A vulnerability was determined in Wavlink WL-NU516U1 V240425. This affects the function sub_405AF4 of the file…
CVE-2026-2615 — High (CVSS 7.2): A flaw has been found in Wavlink WL-NU516U1 up to 20251208. The affected element is the function…
CVE-2026-2567 — High (CVSS 7.2): A vulnerability was detected in Wavlink WL-NU516U1 20251208. This vulnerability affects the function sub_401218 of the…
CVE-2026-2565 — Medium (CVSS 6.6): A weakness has been identified in Wavlink WL-NU516U1 20251208. Affected by this issue is the function sub_40785C of the…

All CVEs affecting Wavlink Wl-nu516u1 Firmware →

Other CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities

CVE-2026-2778 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component. This vulnerability was fixed in…
CVE-2026-2776 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability…
CVE-2025-1866 — Critical (CVSS 10.0): Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in warmcat libwebsockets allows…
CVE-2022-27625 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
CVE-2022-27624 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
CVE-2020-11896 — Critical (CVSS 10.0): The Treck TCP/IP stack before 6.0.1.66 allows Remote Code Execution, related to IPv4 tunneling.

Browse all CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities →