What is CVE-2026-2379?

CVE-2026-2379 is a medium-severity vulnerability in Arista Networks Eos, classified under Operation on a Resource after Expiration or Release. CVSS score: 5.9/10. Published 2026-06-05.

How severe is CVE-2026-2379?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Vulnerability in Arista Networks Eos

CVE-2026-2379

On affected platforms with hardware IPSec support running Arista EOS with certain IPsec features enabled, EOS may exhibit unexpected behavior in specific cases. Physical interface flaps and certain agent restarts can cause IPsec tunnel re-establishment with existing Security Associations, resulting in sequence number mismatches between tunnel endpoints potentially causing unstable communication.

Published 2026-06-05 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.002 (12.4th percentile), scored 2026-10-19.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 12th percentile — 12.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

Arista Networks Eos — versions 4.34.0, 4.33.0M, 4.32.0M

Weakness classification (CWE)

CWE-672 — Operation on a Resource after Expiration or Release

References

www.arista.com/en/support/advisories-notices/security-advisory/23419-security-a… (vendor-advisory)

Frequently asked questions

What is CVE-2026-2379?: CVE-2026-2379 is a medium-severity vulnerability in Arista Networks Eos, classified under Operation on a Resource after Expiration or Release. CVSS score: 5.9/10. Published 2026-06-05.
How severe is CVE-2026-2379?: Medium severity. CVSS v3 base score is 5.9 out of 10.