CVE-2026-4961 Tenda AC6 POST Request QuickIndex formQuickIndex stack-based overflow

High 8.7 Published 27 Mar 2026 Updated 27 Mar 2026

Remote attackers can trigger a stack-based buffer overflow in the Tenda AC6 router via a crafted POST request, 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-2026-4961?

CVE-2026-4961 is a high-severity memory corruption vulnerability in Tenda Ac6 Firmware, published on 27 Mar 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 AC6 15.03.05.16. Affected by this vulnerability is the function formQuickIndex of the file /goform/QuickIndex of the component POST Request Handler. The manipulation of the argument PPPOEPassword leads to stack-based buffer overflow. The attack is possible to be carried out remotely. The exploit is publicly available and might be used.

Weakness: CWE-121, CWE-787, CWE-119

Which versions are affected by CVE-2026-4961?

It affects 1 product.

Products include Tenda Ac6 Firmware.

How do I fix CVE-2026-4961?

No fix has been published for CVE-2026-4961 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-2026-4961 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-4961 exists.

All Tenda Ac6 Firmware vulnerabilities

Sources

Also known as GHSA-qhww-r997-h23m.