What is CVE-2026-77191?

CVE-2026-77191 is a low-severity vulnerability in Arista Networks Eos, classified under Missing Authorization. CVSS score: 2.6/10. Published 2026-09-14.

How severe is CVE-2026-77191?

Low severity. CVSS v3 base score is 2.6 out of 10.

Auth bypass in Arista Networks Eos

CVE-2026-77191

An authenticated supplicant on an adjacent network may bypass intended network authorization policy and send unrestricted traffic during a brief window (milliseconds to seconds) between the completion of the authentication phase and the full enforcement of its assigned ACL.

Vulnerability class: Broken Access Control

CVSS v3 metric

CVSS v3 base score 2.6 (Low). Vector: CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N.

Affected products

Arista Networks Eos

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

psirt@arista.com

Frequently asked questions

What is CVE-2026-77191?: CVE-2026-77191 is a low-severity vulnerability in Arista Networks Eos, classified under Missing Authorization. CVSS score: 2.6/10. Published 2026-09-14.
How severe is CVE-2026-77191?: Low severity. CVSS v3 base score is 2.6 out of 10.