CVSS 4.0
8.3 highCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:NCVE-2026-121290 Security Advisory 0209
High (8.3) in arista networks eos. EPSS 0.4% estimated probability of exploitation activity in the next 30 days.
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.
Severity
CVSS 3.1
8.2 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H- EPSS
- 0.4% estimated probability of exploitation activity in the next 30 days; 30th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: yes · Technical impact: partial, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-420 Unprotected Alternate Channel
- Published
- Modified
- Assigned by
- Arista (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
- arista networks:eos
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| Arista Networks EOS | from 4.36.0F through 4.36.2F |
| Arista Networks EOS | from 4.35.0F through 4.35.6M |
| Arista Networks EOS | from 4.34.0F through 4.34.8M |
| Arista Networks EOS | from 4.33.0F through 4.33.10M |
| Arista Networks EOS | from 4.32.0F before 4.33.0F |
| Arista Networks EOS | from 1.0.0 before 4.32.0F |