Is there a public exploit for CVE-2026-121290?

No public exploit for CVE-2026-121290 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-121290?

CVE-2026-121290 scores CVSS 8.3 (v4.0), rated high. EPSS puts the chance of exploitation in the next 30 days at 0.36%.

What does CVE-2026-121290 affect?

CVE-2026-121290 affects Arista Networks EOS.

8.3 High

On affected platforms running Arista EOS with Border Gateway Protocol (BGP) changing the BGP listen port from its default value disables…

CVE-2026-121290

On affected platforms running Arista EOS with Border Gateway Protocol (BGP) changing the BGP listen port from its default value disables default protective Access Control List (ACL) rules against unexpected BGP peering attempts.

Assessment

CVSS: 8.3 (v4.0)
Severity: High
EPSS: 0.36% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 10 November 2026
Last updated: 13 November 2026
Affected: Arista Networks · EOS
Assigner: Arista

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

https://www.arista.com/en/support/advisories-notices/security-advisory/25031-security-advisory-0209

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