What is CVE-2021-28495?

CVE-2021-28495 is a high-severity vulnerability in Arista 7130, classified under Improper Authentication. CVSS score: 7.2/10. Published 2021-09-09.

How severe is CVE-2021-28495?

High severity. CVSS v3 base score is 7.2 out of 10.

Auth bypass in Arista 7130

CVE-2021-28495

In Arista's MOS (Metamako Operating System) software which is supported on the 7130 product line, under certain conditions, user authentication can be bypassed when API access is enabled via the JSON-RPC APIs. This issue affects: Arista Metamako Operating System All releases in the MOS-0.1x train MOS-0.13 and post releases in the MOS-0.1x train MOS-0.26.6 and below releases in the MOS-0.2x train MOS-0.31.1 and below releases in the MOS-0.3x train

Vulnerability class: Broken Authentication

Published 2021-09-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:L.

EPSS exploit prediction

EPSS: 0.009 (60.2th percentile), scored 2026-10-24.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 60.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Arista 7130
Arista Metamako Operating System — versions MOS-0.13, MOS-0.26.7, MOS-0.32.0
Arista Metamako Operating System

Weakness classification (CWE)

CWE-287 — Improper Authentication

References

www.arista.com/en/support/advisories-notices/security-advisories/12914-security… (Mitigation, Vendor Advisory)

Frequently asked questions

What is CVE-2021-28495?: CVE-2021-28495 is a high-severity vulnerability in Arista 7130, classified under Improper Authentication. CVSS score: 7.2/10. Published 2021-09-09.
How severe is CVE-2021-28495?: High severity. CVSS v3 base score is 7.2 out of 10.