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Vulnerability record · CVE-2021-28503 · published 4 February 2022

CVE-2021-28503: Arista eos improper authentication vulnerability

Arista · Eos

The impact of this vulnerability is that Arista's EOS eAPI may skip re-evaluating user credentials when certificate based authentication is used, which allows remote attackers to access the device via eAPI.

9.8 CVSS 3.1 Critical EPSS 0.74% · top 47.4% CWE-305 · CWE-305CWE-287 · Improper authentication
9.8CVSS 3.1 base score, v2 6.8
0.74%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

The impact of this vulnerability is that Arista's EOS eAPI may skip re-evaluating user credentials when certificate based authentication is used, which allows remote attackers to access the device via eAPI.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://www.arista.com/en/support/advisories-notices/security-advisories/13605-security-advisory-0072 MitigationPatchVendor Advisory
https://www.arista.com/en/support/advisories-notices/security-advisories/13605-security-advisory-0072 MitigationPatchVendor Advisory

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Source: NIST National Vulnerability Database (record CVE-2021-28503), CISA KEV, FIRST EPSS (scores of 2026-09-29). This page is refreshed as NVD updates the record.