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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
2026-07-22
Advisory published
2026-06-04
Advisory updated
2026-07-22

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.

Sources and references

Verified primary and authoritative sources

  • CVE-2024-6858 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2024-6858

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2024-6858 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2024-6858

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source reference

    Unverified legacy reference

    URL: https://www.arista.com/en/support/advisories-notices/security-advisory/19917-security-advisory-0103

    [email protected]

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.