CVE-2021-28510 json
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.
published 2023-01-24 3 y ago modified 2026-06-17 4 mo ago also EUVD-2021-15186
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 63%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- arista eos 4.23.10, 4.24.8, 4.25.6, 4.26.4, 4.27.1
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 19 mo ago
Exploit prediction
1.01% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- arista.com https://www.arista.com/en/support/advisories-notices/security-advisory/15439-security-advisory-0076 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected products
- Arista Networks EOS
Classification
References
-
arista.com
/en/support/advisories-notices/security-advisory/15439-security-advisory-0076
exploit, mitigation, vendor-advisory
Sources
- CVE List CVE-2021-28510
- NVD CVE-2021-28510
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