Vulnerability · Published Sep 16, 2026 · Assigned by Arista

CVE-2026-19640Security Advisory 0170

Medium 4.2

In plain English

A medium-severity incorrect authorization in EOS from Arista Networks. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 10% of all known vulnerabilities).

Severity (CVSS 3.1)4.2Medium

Exploit odds (30 days)0.2%top 90.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

On affected platforms running Arista EOS, an authenticated user with access to the gNMI (gRPC Network Management Interface) may receive incorrect authorization results, potentially allowing access beyond their currently assigned permissions. This issue was discovered internally by Arista and the company is not aware of any malicious uses of this issue in customer networks.

Affected products (as reported)

Vendor	Product	Versions
Arista Networks	EOS	4.36.0F – through 4.36.0.1F4.35.0F – through 4.35.5M4.34.0F – through 4.34.7M4.33.0F – through 4.33.8M4.24.0F – before 4.33.0F

Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N

References

Security Advisory 0170 vendor-advisory