Medium severity · published Sep 16, 2026
CVE-2026-73463
On affected platforms running Arista EOS, when multiple gRPC Network Security Interface (gNSI) transports are configured, a race condition in the gNSI Authz service may cause a policy rotation to fail
5.3
CVSS
0.2%
EPSS
No
On KEV
Description
On affected platforms running Arista EOS, when multiple gRPC Network Security Interface (gNSI) transports are configured, a race condition in the gNSI Authz service may cause a policy rotation to fail silently. An authenticated user whose access was revoked by the new policy may retain unauthorized access to gRPC interfaces. This does not affect Bootz.
This issue was discovered internally by Arista, and the company is not aware of any malicious exploitation of this vulnerability in customer networks.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 12% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EO
EOS · Arista Networks
4.36.0F through 4.36.0.1F; 4.35.0F through 4.35.5M; 4.34.0F through 4.34.7M; 4.33.0F through 4.33.8M; 4.32.0F through 4.32.11M; 4.31.0F through 4.31.10M · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-73463
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-73463
www.arista.com
https://www.arista.com/en/support/advisories-notices/security-advisory/24725-security-advisory-0169
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