Is CVE-2026-121371 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-121371 being exploited in the wild.

How severe is CVE-2026-121371?

High severity, with a CVSS score of 7.5, published 10 November 2026.

Which products and versions are affected?

Arista Eos 4.36.3M and earlier (4.36.x), 4.35.7M and earlier (4.35.x), 4.34.9M and earlier (4.34.x), 4.33.11M and earlier (4.33.x), all 4.32.x and earlier releases.

How is CVE-2026-121371 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-121371?

Check whether you run Arista Eos at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-121371: Arista EOS path traversal in eAPI service

CVE-2026-121371 · Severity: high · CVSS 7.5 · Published 2026-11-10

Arista EOS network switches with the eAPI service enabled are vulnerable to an unauthenticated remote attacker reading arbitrary files, including sensitive credentials stored on the switch. An attacker can send a specially crafted HTTP request to retrieve files from the switch filesystem without needing to log in or interact with a user. This allows attackers to steal administrative credentials and gain full control of the network infrastructure.

Technologies: Arista Eos. Vendors: Arista.

Quick answers

Is CVE-2026-121371 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-121371 being exploited in the wild.
How severe is CVE-2026-121371?: High severity, with a CVSS score of 7.5, published 10 November 2026.
Which products and versions are affected?: Arista Eos 4.36.3M and earlier (4.36.x), 4.35.7M and earlier (4.35.x), 4.34.9M and earlier (4.34.x), 4.33.11M and earlier (4.33.x), all 4.32.x and earlier releases.
Is there a fix for CVE-2026-121371?: No fixed version is recorded yet. Disable the eAPI service or disable the default-service feature if eAPI is not required. Restrict network access to the management interface to trusted administrative networks only. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-121371 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-121371?: Check whether you run Arista Eos at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Disable the eAPI service or disable the default-service feature if eAPI is not required. Restrict network access to the management interface to trusted administrative networks only.

Technical details

A path traversal vulnerability (CWE-22) in the eAPI HTTP service allows unauthenticated remote attackers to read arbitrary files via specially crafted HTTP requests. The vulnerability affects EOS versions with eAPI enabled (default configuration) and requires network access to the management interface. An attacker gains read access to any file on the switch filesystem, including configuration files containing credentials.

Affected products

Arista EOS 4.36.3M and earlier (4.36.x), 4.35.7M and earlier (4.35.x), 4.34.9M and earlier (4.34.x), 4.33.11M and earlier (4.33.x), all 4.32.x and earlier releases

Timeline

2026-11-10: disclosed: Security Advisory 0218 published

References

https://www.arista.com/en/support/advisories-notices/security-advisory/25040-security-advisory-0218

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