This vulnerability involves an operation on a resource after expiration or release (CWE-672) in Arista EOS IPsec implementation. When specific IPsec features are enabled on hardware with IPSec support, physical interface flaps or agent restarts can trigger IPsec tunnel re-establishment with existing Security Associations. This results in sequence number mismatches between tunnel endpoints, potentially causing unstable IPsec communication. The affected EOS versions range from 4.27.1F to 4.34.0. The CVSS 3.1 base score is 5.9, indicating medium severity, with network attack vector, high attack complexity, no privileges required, no user interaction, unchanged scope, high confidentiality impact, no integrity or availability impact. No patch or official remediation guidance is currently available.

The vulnerability can cause unstable communication on IPsec tunnels due to sequence number mismatches after interface flaps or agent restarts. This impacts confidentiality as the IPsec tunnel's security associations may not properly synchronize, but does not affect integrity or availability. There are no known exploits in the wild, and the issue does not appear to allow direct unauthorized access or code execution.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, administrators should monitor IPsec tunnel stability and consider minimizing interface flaps or agent restarts on affected devices where feasible. No official remediation level or temporary fix has been provided by Arista Networks at this time.