PatchSiren cyber security CVE debrief

CVE-2024-6858 Arista Networks CVE debrief

CVE-2024-6858 is a MEDIUM severity vulnerability in Arista's EOS when in 802.1X mode. The vulnerability allows multi-auth unauthenticated hosts to access a switch port if there exists an EAPOL capable device in the fallback VLAN. The CVSS score for this vulnerability is 6.5.

Vendor: Arista Networks
Product: EOS
CVSS: MEDIUM 6.5
CISA KEV: Not listed in stored evidence
Original CVE published: 2026-06-04
Original CVE updated: 2026-06-05
Advisory published: 2026-06-04
Advisory updated: 2026-06-05

Who should care

Administrators and users of Arista EOS devices, particularly those using 802.1X mode, should be aware of this vulnerability and take necessary precautions.

Technical summary

In Arista's EOS when in 802.1X mode, multi-auth unauthenticated hosts might be allowed access to a switch port if there exists an EAPOL capable device in the fallback VLAN.

Defensive priority

MEDIUM

Recommended defensive actions

Review and update Arista EOS configurations to ensure proper 802.1X mode settings.
Implement additional security measures to restrict access to switch ports.
Monitor for and apply patches or updates provided by Arista.

Evidence notes

The vendor for this CVE is likely Arista, based on the provided evidence and reference links.

Official resources

CVE-2024-6858 was published on [cvePublishedAt] and modified on [cveModifiedAt].