CVE-2026-3613 Wavlink WL-NU516U1 login.cgi sub_401A0C stack-based overflow

High 8.6 Published 6 Mar 2026 Updated 9 Mar 2026

A remote attacker can trigger a stack-based buffer overflow in the login.cgi script of Wavlink WL-NU516U1 routers, potentially leading to arbitrary code execution.

Exploited in the wild: Not known
Login needed: An administrator
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-3613?

CVE-2026-3613 is a high-severity memory corruption vulnerability in Wavlink WL-NU516U1, published on 6 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim.

Official description

A vulnerability was identified in Wavlink WL-NU516U1 V240425. This vulnerability affects the function sub_401A0C of the file /cgi-bin/login.cgi. Such manipulation of the argument ipaddr leads to stack-based buffer overflow. It is possible to launch the attack remotely. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure.

Weakness: CWE-121, CWE-119

Which versions are affected by CVE-2026-3613?

It affects 1 product.

Products include Wavlink Wl-Nu516u1 Firmware.

How do I fix CVE-2026-3613?

No fix has been published for CVE-2026-3613 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-3613 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-3613 exists.

Sources

Also known as GHSA-2fhq-mmhr-8hcv.