CVE-2026-73445

Security Advisory 0167

Published Sep 16, 2026 CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed

Description

On affected platforms running Arista EOS, an issue with the gRPC Network Security Interface (gNSI) Authz Rotate RPC may cause an incorrect Authz policy which was uploaded in the ongoing RPC stream to become active. This does not affect Bootz.

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

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Arista Networks

EOS

unaffected

Version	Status	Constraints
`4.36.0F`	affected	≤ 4.36.0.1F
`4.35.0F`	affected	≤ 4.35.5M
`4.34.0F`	affected	≤ 4.34.7M
`4.33.0F`	affected	≤ 4.33.8M
`4.32.0F`	affected	< 4.33.0F
`4.31.0F`	affected	< 4.32.0F

No data.

Vendor Product Versions

Arista

Eos

Version	Status	Scheme	Platform
`[4.36.0F,4.36.0.1F]`	affected	generic	['710_series', '720d_series', '720xp/722xpm_series', '750x_series', '7010tx_series', '7020r/r4_series', '7130_series_running_eos', '7170_series', '7050x3/x4_series', '7060x/x2/x4/x5/x6_series', '7260x/x3_series', '7280r/r2/r3/r4_series', '7300x/x3_series', '7320x_series', '7358x4_series', '7368x4_series', '7388x5_series', '7500r/r2/r3_series', '7800r3/r4_series', '7700r4_series', 'awe_5000_series', 'awe_7200r_series', 'cloudeos', 'ceos-lab', 'veos-lab']
`[4.35.0F,4.35.5M]`	affected	generic	['710_series', '720d_series', '720xp/722xpm_series', '750x_series', '7010tx_series', '7020r/r4_series', '7130_series_running_eos', '7170_series', '7050x3/x4_series', '7060x/x2/x4/x5/x6_series', '7260x/x3_series', '7280r/r2/r3/r4_series', '7300x/x3_series', '7320x_series', '7358x4_series', '7368x4_series', '7388x5_series', '7500r/r2/r3_series', '7800r3/r4_series', '7700r4_series', 'awe_5000_series', 'awe_7200r_series', 'cloudeos', 'ceos-lab', 'veos-lab']
`[4.34.0F,4.34.7M]`	affected	generic	['710_series', '720d_series', '720xp/722xpm_series', '750x_series', '7010tx_series', '7020r/r4_series', '7130_series_running_eos', '7170_series', '7050x3/x4_series', '7060x/x2/x4/x5/x6_series', '7260x/x3_series', '7280r/r2/r3/r4_series', '7300x/x3_series', '7320x_series', '7358x4_series', '7368x4_series', '7388x5_series', '7500r/r2/r3_series', '7800r3/r4_series', '7700r4_series', 'awe_5000_series', 'awe_7200r_series', 'cloudeos', 'ceos-lab', 'veos-lab']
`[4.33.0F,4.33.8M]`	affected	generic	['710_series', '720d_series', '720xp/722xpm_series', '750x_series', '7010tx_series', '7020r/r4_series', '7130_series_running_eos', '7170_series', '7050x3/x4_series', '7060x/x2/x4/x5/x6_series', '7260x/x3_series', '7280r/r2/r3/r4_series', '7300x/x3_series', '7320x_series', '7358x4_series', '7368x4_series', '7388x5_series', '7500r/r2/r3_series', '7800r3/r4_series', '7700r4_series', 'awe_5000_series', 'awe_7200r_series', 'cloudeos', 'ceos-lab', 'veos-lab']
`[4.32.0F,4.33.0F)`	affected	generic	['710_series', '720d_series', '720xp/722xpm_series', '750x_series', '7010tx_series', '7020r/r4_series', '7130_series_running_eos', '7170_series', '7050x3/x4_series', '7060x/x2/x4/x5/x6_series', '7260x/x3_series', '7280r/r2/r3/r4_series', '7300x/x3_series', '7320x_series', '7358x4_series', '7368x4_series', '7388x5_series', '7500r/r2/r3_series', '7800r3/r4_series', '7700r4_series', 'awe_5000_series', 'awe_7200r_series', 'cloudeos', 'ceos-lab', 'veos-lab']
`[4.31.0F,4.32.0F)`	affected	generic	['710_series', '720d_series', '720xp/722xpm_series', '750x_series', '7010tx_series', '7020r/r4_series', '7130_series_running_eos', '7170_series', '7050x3/x4_series', '7060x/x2/x4/x5/x6_series', '7260x/x3_series', '7280r/r2/r3/r4_series', '7300x/x3_series', '7320x_series', '7358x4_series', '7368x4_series', '7388x5_series', '7500r/r2/r3_series', '7800r3/r4_series', '7700r4_series', 'awe_5000_series', 'awe_7200r_series', 'cloudeos', 'ceos-lab', 'veos-lab']

Remediation

Vendor Solution

The recommended resolution is to upgrade to a remediated software version at your earliest convenience. Arista recommends customers move to the latest version of each release that contains all the fixes listed below. CVE-2026-73445 has been fixed in the following releases: - 4.36.1F and later releases in the 4.36.x train - 4.35.6M and later releases in the 4.35.x train - 4.34.8M and later releases in the 4.34.x train - 4.33.9M and later releases in the 4.33.x train No hotfix is available for this issue.

Vendor Workaround

1. Include exactly one UploadRequest in a gNSI Authz Rotate request. 2. Use a gNSI Authz policy that restricts gNSI Authz use to only those who strictly need it. Below is an example policy that only allows user "Neo" to rotate Authz policies: { "name":"restrict-authz-policy", "allow_rules":[ { "name":"neoallow", "request":{ "paths":[ "/gnsi.authz.v1.Authz/Rotate" ], "headers":[ { "key":"username", "values":[ "Neo" ] } ] } }, { "name":"allow-gnmi", "request":{ "paths":[ "/gnmi.gNMI/*" ] } }, { "name":"allow-gnoi", "request":{ "paths":[ "/gnoi.*" ] } } ] } Ideally, this policy would be uploaded via a gNSI client for correct version and created-on metadata handling. However, the policy can also be written directly to the active policy file: switch#bash timeout 100 echo "{\"name\":\"restrict-authz-policy\",\"allow_rules\":[{\"name\":\"neoallow\",\"request\":{\"paths\":[\"\/gnsi.authz.v1.Authz\/Rotate\"],\"headers\":[{\"key\":\"username\",\"values\":[\"Neo\"]}]}},{\"name\":\"allow-gnmi\",\"request\":{\"paths\":[\"\/gnmi.gNMI\/*\"]}},{\"name\":\"allow-gnoi\",\"request\":{\"paths\":[\"\/gnoi.*\"]}}]}" | sudo tee /persist/sys/gnsi/authz/policy.json && sleep 11

Tracking

Advisories

No advisories available

Metrics

Attack Vector Network

Attack Complexity Low

Privileges Required High

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required High

Scope Unchanged

Confidentiality Impact None

Integrity Impact High

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.350% probability within 30 days)

Exploitation none

Automatable no

Technical Impact partial

References

Link	Providers
https://www.arista.com/en/support/advisories-notices/security-advisory/24723-security-advisory-0167

History

Sep 17, 2026 9:15 PM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Arista Arista eos
Vendors & Products		Arista Arista eos

Sep 16, 2026 6:30 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Sep 16, 2026 9:15 AM Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		On affected platforms running Arista EOS, an issue with the gRPC Network Security Interface (gNSI) Authz Rotate RPC may cause an incorrect Authz policy which was uploaded in the ongoing RPC stream to become active. This does not affect Bootz. This issue was discovered internally by Arista and the company is not aware of any malicious uses of this issue in customer networks.
Title		Security Advisory 0167
Weaknesses		CWE-20
References		https://www.arista.com/en/support/advisories-notices/security-advisory/24723-security-advisory-0167
Metrics		cvssV3_1 `{'score': 4.9, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N'}` cvssV4_0 `{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N'}`