What is CVE-2026-6559?

CVE-2026-6559 is a medium-severity vulnerability in Wavlink Wl-Wn579a3, classified under Cross-site Scripting. CVSS score: 4.3/10. Published 2026-04-19.

How severe is CVE-2026-6559?

Medium severity. CVSS v3 base score is 4.3 out of 10.

RCE in Wavlink Wl-Wn579a3

CVE-2026-6559

A weakness has been identified in Wavlink WL-WN579A3 220323. This affects the function sub_401F80 of the file /cgi-bin/login.cgi. This manipulation of the argument Hostname causes cross site scripting. Remote exploitation of the attack is possible. Upgrading the affected component is recommended. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2026-04-19 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.004 (36.5th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 36.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.002

Affected products

Wavlink Wl-Wn579a3 — versions 220323

Weakness classification (CWE)

References

vuldb.com/vuln/358196 (technical-description, vdb-entry)
vuldb.com/vuln/358196/cti (signature, permissions-required)
vuldb.com/submit/785303 (third-party-advisory)
github.com/Litengzheng/vul_db/blob/main/WL-WN579A3/vul_16/README.md (broken-link)
dl.wavlink.com/firmware/RD/WINSTAR_WN579A3-A-2026-03-10-94f93d4-WO-mt7628-squas… (patch)

Frequently asked questions

What is CVE-2026-6559?: CVE-2026-6559 is a medium-severity vulnerability in Wavlink Wl-Wn579a3, classified under Cross-site Scripting. CVSS score: 4.3/10. Published 2026-04-19.
How severe is CVE-2026-6559?: Medium severity. CVSS v3 base score is 4.3 out of 10.