CVE-2024-27891
Awaiting Analysis Awaiting Analysis - Queue
MACsec and Egress ACL Bypass in Arista EOS

Publication date: 2026-06-04

Last updated on: 2026-06-04

Assigner: Arista Networks, Inc.

Description
On affected platforms running Arista EOS with MACsec and egress ACLs configured on the same interfaces, the ACL policies may not be enforced for packets egressing on those ports. This can cause outgoing packets to incorrectly be allowed or denied.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-06-04
Last Modified
2026-06-04
Generated
2026-06-25
AI Q&A
2026-06-05
EPSS Evaluated
2026-06-24
NVD
CVE-2024-27891
EUVD
EUVD-2024-55611
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
arista arista_eos *
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-284 The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.
Attack-Flow Graph
AI Quick Actions
Instant insights powered by AI
Executive Summary

This vulnerability occurs on Arista EOS platforms when MACsec and egress ACLs are configured on the same interfaces. Due to this issue, the ACL policies may not be properly enforced on outgoing packets, meaning that packets leaving the affected ports might be incorrectly allowed or denied.

Impact Analysis

The impact of this vulnerability is that network security policies enforced by egress ACLs may not function correctly. This can lead to unauthorized data being sent out or legitimate data being blocked, potentially causing security breaches or disruptions in network communication.

Chat Assistant
Ask questions about this CVE
Hi! I’m here to help you understand CVE-2024-27891. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70
EPSS Chart