CVE-2020-26139 Missing authorization in n/a

Medium 5.3 Published 11 May 2021 Updated 14 Apr 2026

NetBSD kernel allows unauthenticated EAPOL frame forwarding, enabling denial-of-service attacks against Wi-Fi clients and facilitating further exploitation.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2020-26139?

CVE-2020-26139 is a medium-severity missing authorization vulnerability in Debian Debian Linux, published on 11 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

An issue was discovered in the kernel in NetBSD 7.1. An Access Point (AP) forwards EAPOL frames to other clients even though the sender has not yet successfully authenticated to the AP. This might be abused in projected Wi-Fi networks to launch denial-of-service attacks against connected clients and makes it easier to exploit other vulnerabilities in connected clients.

Weakness: CWE-287

Which versions are affected by CVE-2020-26139?

It affects 166 products.

Products include Arista C-100 Firmware, Arista C-110 Firmware, Arista C-120 Firmware, Arista C-130 Firmware, Arista C-200 Firmware, Arista C-230 Firmware and 160 more.

How do I fix CVE-2020-26139?

Apply the vendor's patch.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2020-26139 being exploited?

There is no known exploitation of CVE-2020-26139 in the wild and no public exploit code.

All Debian Debian Linux vulnerabilities

Sources

Also known as 2860248, 2867013, 2868054, 2888227, 2888467, 2942096 and 6 more.