CVE-2026-121295
Security Advisory 0223
On affected platforms running Arista EOS configured as S-BFD peers, an unauthenticated attacker could send a crafted S-BFD PDU to an initiator device. This crafted PDU could cause the kernel on the initiator device to crash, resulting in an unexpected device reboot.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| EOS Arista Networks Platforms: 710 Series, 720D Series, 720XP/722XPM Series, 750X Series, 7010TX Series, 7020R/R4 Series, 7280R/R2/R3/R4 Series, 7500R/R2/R3 Series, 7800R3/R4 Series, 7700R4 Series, CloudEOS, cEOS-lab, vEOS-lab, CloudVision eXchange, virtual or physical appliance |
≥ 4.36.0F; ≤ 4.36.2F (affected, custom) ≥ 4.35.0F; ≤ 4.35.6M (affected, custom) ≥ 4.34.0F; ≤ 4.34.8M (affected, custom) ≥ 4.33.0F; ≤ 4.33.10M (affected, custom) ≥ 4.32.0F; < 4.33.0F (affected, custom) ≥ 1.0.0; < 4.32.0F (affected, custom) Other versions: unaffected |
CNA: Arista |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 8.6 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H | CNA: Arista |
| 4.0 / 9.2 critical |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H | CNA: Arista |
| 4.0 / 9.2 critical |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X | NVD: [email protected] |
| 3.1 / 8.6 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H | NVD: [email protected] |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
For agents and automation
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