CVE-2026-5004: Wavlink WL-WN579X3-C UPNP firewall.cgi sub_4019FC stack-based overflow

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-03-28 · updated 2026-06-17
Weakness: CWE-119

Description

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.

Affected products

Wavlink WL-WN579X3-C: 231124

References

https://github.com/Litengzheng/vul_db/blob/main/WL-WN579X3-C/vul_200/README.md
https://vuldb.com/submit/779149
https://vuldb.com/vuln/353891
https://vuldb.com/vuln/353891/cti

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