Arista EOS up to 4.36.1F SNMP improper authorization

Summaryinfo

A vulnerability was found in Arista EOS up to 4.32.x/4.33.9M/4.34.7.1M/4.35.5M/4.36.1F. It has been rated as critical. This impacts an unknown function of the component SNMP. This manipulation causes improper authorization. This vulnerability is handled as CVE-2026-73440. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Arista EOS up to 4.32.x/4.33.9M/4.34.7.1M/4.35.5M/4.36.1F. It has been declared as critical. Affected by this vulnerability is an unknown function of the component SNMP. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

On affected platforms running Arista EOS with Simple Network Management Protocol (SNMP) configured, SNMPv3 local or remote user credentials may be exposed as a one-way hashed, localized key value within the device's running and sanitized configurations. An authenticated user who gains access to this sensitive information could leverage it to perform unauthorized read operations on SNMP tables or to send fraudulent trap notifications to the Network Management System (NMS). This issue was discovered internally by Arista, and the company is not aware of any malicious exploitation of this vulnerability in customer networks.

The advisory is shared at arista.com. This vulnerability is known as CVE-2026-73440 since 08/12/2026. The exploitation appears to be easy. The attack can be launched remotely. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1548.002 for this issue.

Upgrading to version 4.33.0F eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• Arista

Name

• EOS

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8
• 4.9
• 4.10
• 4.11
• 4.12
• 4.13
• 4.14
• 4.15
• 4.16
• 4.17
• 4.18
• 4.19
• 4.20
• 4.21
• 4.22
• 4.23
• 4.24
• 4.25
• 4.26
• 4.27
• 4.28
• 4.29
• 4.30
• 4.31
• 4.32
• 4.33.9M
• 4.34.7.1M
• 4.35.5M
• 4.36.1F

License

• commercial

CPE 2.3info

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CPE 2.2info

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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