Critical severity · published Sep 16, 2026
CVE-2026-73456
Under certain circumstances, an unauthenticated gNPSI client can craft a malicious request to allow arbitrary code execution, granting an attacker full administrative control over the compromised switch.
10.0
CVSS
0.7%
EPSS
No
On KEV
Description
Under certain circumstances on affected platforms running Arista EOS with gRPC Network Packet Sampling Interface (gNPSI) enabled, an unauthenticated gNPSI client can craft a malicious request to allow arbitrary code execution, granting an attacker full administrative control over the compromised switch.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 53% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EO
EOS · Arista Networks
4.36.0 through 4.36.1F; 4.35.0 through 4.35.5M; 4.34.2F through 4.34.7M · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-73456
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-73456
www.arista.com
https://www.arista.com/en/support/advisories-notices/security-advisory/24714-security-advisory-0158
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