CVE-2026-2140 Tenda TX9 setMacFilterCfg sub_4223E0 buffer overflow

High 8.7 Published 8 Feb 2026 Updated 23 Feb 2026

Remote attackers can trigger a buffer overflow in the Tenda TX9 router's MAC filter configuration, potentially leading to arbitrary code execution.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-2140?

CVE-2026-2140 is a high-severity memory corruption vulnerability in Tenda TX9, published on 8 Feb 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

A vulnerability was identified in Tenda TX9 up to 22.03.02.10_multi. Affected by this issue is the function sub_4223E0 of the file /goform/setMacFilterCfg. Such manipulation of the argument deviceList leads to buffer overflow. The attack may be launched remotely. The exploit is publicly available and might be used.

Weakness: CWE-120, CWE-119

Which versions are affected by CVE-2026-2140?

It affects 1 product.

Products include Tenda Tx9 Firmware.

How do I fix CVE-2026-2140?

No fix has been published for CVE-2026-2140 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-2026-2140 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-2140 exists.

Sources

Also known as GHSA-qmm8-vq32-mvfg.