Buffer overflow in Wavlink Wl-Wn579x3-C

CVE-2026-5004

A vulnerability was determined in Wavlink WL-WN579X3-C 231124. This impacts the function sub_4019FC of the file /cgi-bin/firewall.cgi of the component UPNP Handler. Executing a manipulation of the argument UpnpEnabled can lead to stack-based buffer overflow. It is possible to launch the attack remotely. The exploit has been publicly disclosed and may be utilized. The vendor was contacted early about this disclosure but did not respond in any way.

Vulnerability class: Buffer Overflow

EPSS: 0.007 (49.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

  • cna@vuldb.com (technical-description, VDB Entry, Third Party Advisory, vdb-entry)
  • cna@vuldb.com (signature, Permissions Required, permissions-required, VDB Entry)
  • cna@vuldb.com (VDB Entry, Third Party Advisory, third-party-advisory)
  • cna@vuldb.com (Exploit, Third Party Advisory, exploit)

Frequently asked questions

What is CVE-2026-5004?
CVE-2026-5004 is a high-severity vulnerability in Wavlink Wl-Wn579x3-C, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.8/10. Published 2026-03-28.
How severe is CVE-2026-5004?
High severity. CVSS v3 base score is 8.8 out of 10.