Cyber Resilience

CVE-2026-3662

MediumPublic PoC

Published: 07 March 2026

Published
07 March 2026
Modified
10 March 2026
KEV Added
Patch
CVSS Score v4 5.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0024 47.8th percentile
Risk Priority 10 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-3662 is a medium-severity Injection (CWE-74) vulnerability in Wavlink Wl-Nu516U1 Firmware. Its CVSS base score is 5.1 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 47.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-2 (Flaw Remediation).

Deeper analysis

CVE-2026-3662 is a command injection vulnerability in the Wavlink WL-NU516U1 device running firmware version 240425. The issue resides in the usb_p910 function within the /cgi-bin/adm.cgi script, where manipulation of the Pr_mode argument enables arbitrary command execution. Classified under CWE-74 and CWE-77, it carries a CVSS v3.1 base score of 4.7 (AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L) and was published on 2026-03-07.

The vulnerability can be exploited remotely over the network with low complexity and no user interaction required, but demands high privileges (PR:H) from the attacker. Successful exploitation allows limited impacts: low confidentiality (C:L), integrity (I:L), and availability (A:L) violations through injected commands, potentially enabling unauthorized actions within the device's privileged context.

Advisories from VulDB and a related GitHub repository detail the vulnerability, noting that the exploit has been publicly disclosed and may be actively used. The vendor was contacted early regarding the issue, though no specific patches or mitigations are outlined in the available references.

The public disclosure of the exploit code heightens the risk for unpatched Wavlink WL-NU516U1 devices.

EU & UK References

Vulnerability details

A vulnerability has been found in Wavlink WL-NU516U1 240425. This vulnerability affects the function usb_p910 of the file /cgi-bin/adm.cgi. Such manipulation of the argument Pr_mode leads to command injection. It is possible to launch the attack remotely. The exploit has…

more

been disclosed to the public and may be used. The vendor was contacted early about this disclosure.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
Why these techniques?

Command injection in exposed CGI web interface (adm.cgi) directly enables remote exploitation of a public-facing application (T1190) and results in arbitrary Unix shell command execution on the Linux-based firmware (T1059.004).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

CVEs Like This One

CVE-2026-3661Same product: Wavlink Wl-Nu516U1
CVE-2026-2615Same product: Wavlink Wl-Nu516U1
CVE-2026-3612Same product: Wavlink Wl-Nu516U1
CVE-2026-8191Same product: Wavlink Wl-Nu516U1
CVE-2026-8227Same product: Wavlink Wl-Nu516U1
CVE-2026-8190Same product: Wavlink Wl-Nu516U1
CVE-2026-8188Same product: Wavlink Wl-Nu516U1
CVE-2026-8192Same product: Wavlink Wl-Nu516U1
CVE-2026-8228Same product: Wavlink Wl-Nu516U1
CVE-2026-8189Same product: Wavlink Wl-Nu516U1

Affected Assets

wavlink
wl-nu516u1 firmware
m16u1_v240425

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly blocks command injection by validating/sanitizing the Pr_mode argument before it reaches usb_p910 in adm.cgi.

prevent

Restricts the high-privilege accounts that can reach the vulnerable /cgi-bin/adm.cgi endpoint, reducing the attack surface.

prevent

Requires timely patching or firmware updates to eliminate the publicly disclosed command-injection flaw in the Wavlink device.

References