CVE-2026-77191 — All of the CVEs covered in this advisory apply to affected platforms running Arista EOS with 802.1X authentication an…

CVE-2026-77191

All of the CVEs covered in this advisory apply to affected platforms running Arista EOS with 802.1X authentication and authorization enabled and Access Control Lists (ACLs) configured for per-supplicant policy enforcement. An authenticated supplicant on an PUBLISHED

Description (CNA)

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.

Affected (CNA)

Vendor / product	Versions
Arista Networks / EOS	affected 4.35.0 through 4.35.0.3F; affected 4.34.0 through 4.34.5M; affected 0.0.0 through 4.33.7.1M

CWE

CWE-862

References

https://www.arista.com/en/support/advisories-notices/security-advisory/24706-security-advisory-0150

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.