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.
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
Install ACL rules to drop PTP packets from untrusted sources. Best practice is to block access to untrusted (non-management) networks.
| Product | Vulnerable range | Fixed version | Advisory |
|---|---|---|---|
| Arista Networks EOS | >=4.23.10<=4.23.0 | 4.23.0 | advisory ↗ |
| Arista Networks EOS | >=4.24.8<=4.24.0 | 4.24.0 | advisory ↗ |
| Arista Networks EOS | >=4.25.6<=4.25.0 | 4.25.0 | advisory ↗ |
| Arista Networks EOS | >=4.26.4<=4.26.0 | 4.26.0 | advisory ↗ |
| Arista Networks EOS | >=4.27.1<=4.27.0 | 4.27.0 | advisory ↗ |