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

LOW
2.6
CVSS Score
Published: September 14, 2026 at 10:06 PM UTC
Updated: September 16, 2026 at 08:54 PM UTC
1 product affected across 1 vendorArista EOS

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Severity
LOW2.6
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

0.0.0 ≤ v ≤ 4.33.7.1M4.34.0 ≤ v ≤ 4.34.5M4.35.0 ≤ v ≤ 4.35.0.3F0.0.04.34.04.35.0

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

2.6LOWArista
Attack Vector
ADJACENT_NETWORK
Complexity
HIGH
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-862

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