CVSS 4.0
9.3 criticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NCVE-2026-121289 Security Advisory 0208
Critical (9.3) in arista networks eos. EPSS 0.6% estimated probability of exploitation activity in the next 30 days.
On affected platforms running Arista EOS with BGP configured, a specially crafted packet can cause the BGP agent to crash.
Successful exploitation causes the BGP agent process to terminate, resulting in the loss of all BGP sessions on the affected device and possible disruption to network routing until the process recovers. Due to the nature of the vulnerability, it may also be possible for a sophisticated attacker to achieve arbitrary code execution, which could compromise the confidentiality and integrity of the affected system.
Severity
CVSS 3.1
9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- EPSS
- 0.6% estimated probability of exploitation activity in the next 30 days; 51st 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: total, 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-121 Stack-based Buffer Overflow
- 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 4.25.1F before 4.33.0F |