Authorization bypass via conflicting Pathz principal rules
Published Sep 16, 2026 · Updated Sep 16, 2026
Authorization bypass in affected Arista EOS releases allows remote authenticated users to read or write restricted gNMI paths. gNMI evaluates Pathz policies incorrectly when a group rule and a user rule address the same path, granting permissions that the policy intends to deny. Exploitation requires a running gNMI transport, enabled gNSI Pathz service, a policy containing both rule types for one path, and valid user authentication.
Summary
What happened
Authorization bypass in affected Arista EOS releases allows remote authenticated users to read or write restricted gNMI paths. gNMI evaluates Pathz policies incorrectly when a group rule and a user rule address the same path, granting permissions that the policy intends to deny. Exploitation requires a running gNMI transport, enabled gNSI Pathz service, a policy containing both rule types for one path, and valid user authentication.
The record
- CVE
- CVE-2026-73439
- Published
- Sep 16, 2026
- Updated
- Sep 16, 2026
- Vendor
- Arista Networks
- Product
- Arista EOS
- Classifications
- CWE-842, T1210
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 16, 2026CVE publishedPublication date reported by the CVE source.
- Sep 16, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=4.33.2F <=4.33.8M
- Affected versionversion=4.34.0F <=4.34.6M
- Affected versionversion=4.35.0F <=4.35.5M
- Affected versionversion=4.36.0F <=4.36.0.1F
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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