CVE-2021-28510
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.
02 Description
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.
03 Exploitation and scoring
- Exploitation
- Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.
- SSVC decision
- ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
- AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 1.00% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 62.5% of scored records. A rank, not a probability.
- NVD base score
- 7.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-06-17.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2023-01-24 00:00Z3 YR AGO
- Last updated
- 2025-04-01 18:44Z1 YR AGO
- Reserved
- 2021-03-16
- Assigning CNA
- Arista
- Record state
- PUBLISHED
- Severity
- Medium (CVSS 5.3)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- Weaknesses
- Data version
- 5.1
- Document digest
- f2b5db0440eee4fbbbb4f3a7329e7dbc46259af7e8b7949d85aa09a8ce202d35
05 Affected products
06 References
07 Remediation
The recommended resolution is to upgrade to a remediated software version at your earliest convenience. Artista recommends customers move to the latest version of each release that contains all the fixes listed below. CVE-2021-28510 has been fixed in the following releases: 4.27.2 and later releases in the 4.27.x train 4.26.5 and later releases in the 4.26.x train 4.25.7 and later releases in the 4.25.x train 4.24.9 and later releases in the 4.24.x train 4.23.11 and later releases in the 4.23.x train
Hotfix The following hotfix can be applied to remediate CVE-2021-28510 Note: Installing/uninstalling the SWIX will cause the PTP agent to restart. Version: 1.0 URL:SecurityAdvisory76_CVE-2021-28510_Hotfix.swix SWIX hash: (SHA-512)2b78b8274b7c73083775b0327e13819c655db07e22b80038bb3843002c679a798b53a4638c549a86183e01a835377bf262d27e60020a39516a5d215e2fadb437