CVE-2021-28510: Arista Eos

High severity, CVSS 7.5. EPSS: 1% chance of exploitation in the next 30 days.

For certain systems running EOS, a Precision Time Protocol (PTP) packet of a management/signaling message with an invalid Type-Length-Value (TLV) causes the PTP agent to restart. Repeated restarts of the service will make the service unavailable.

Affected products

• Arista Eos: before 4.23.10 (fixed in 4.23.10); from 4.24.0, before 4.24.8 (fixed in 4.24.8); from 4.25.0, before 4.25.6 (fixed in 4.25.6); from 4.26.0, before 4.26.4 (fixed in 4.26.4); from 4.27.0, before 4.27.1 (fixed in 4.27.1)

Published 2023-01-26. Last modified 2026-06-17.