CVE-2026-4861: Wavlink WL-NU516U1 nas.cgi ftext stack-based overflow

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-03-26 · updated 2026-06-17
Weakness: CWE-119

Description

A weakness has been identified in Wavlink WL-NU516U1 260227. This vulnerability affects the function ftext of the file /cgi-bin/nas.cgi. This manipulation of the argument Content-Length causes stack-based buffer overflow. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.

Affected products

Wavlink NU516U1: m16u1_v260227

References

https://github.com/Wlz1112/WAVLINK-NU516U1-V260227/blob/main/Content-Length.md
https://vuldb.com/?ctiid.353192
https://vuldb.com/?id.353192
https://vuldb.com/?submit.776217

Get alerted when CVE-2026-4861 or the next vulnerability affects your stack