CVE-2021-28495: Arista Metamako Operating System

Critical severity, CVSS 9.8. EPSS: 0.9% chance of exploitation in the next 30 days.

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

Affected products

• Arista Metamako Operating System: from 0.10.0, up to and including 0.13.0; from 0.20.0, up to and including 0.26.7; from 0.30.0, before 0.32.0 (fixed in 0.32.0)

Published 2021-09-09. Last modified 2026-06-17.