---
id: "CVE-2026-121294"
page: "https://infrastack.ai/live/CVE-2026-121294"
kind: "vulnerability"
aliases: ["CVE-2026-121294"]
title: "Arista EOS: crafted S-BFD packet can stop reflector proxy from reflecting"
severity: "medium"
cvss: 6.9
epss: null
exploited: false
status: "open"
category: "vendor"
products: []
ecosystems: []
tags: ["arista-eos", "network-devices", "s-bfd", "vendor"]
not_affected_if: ["default-config", "no-sbfd-reflector-proxy"]
published_at: "2026-11-10T20:18:55+00:00"
first_seen_at: "2026-11-10T20:46:04+00:00"
updated_at: "2026-11-10T20:47:59+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-121294", "first_seen_at": "2026-11-10T20:46:04+00:00"}]
exploit_sources: []
---

# Arista EOS: crafted S-BFD packet can stop reflector proxy from reflecting

Link for people: https://infrastack.ai/live/CVE-2026-121294 (this .md is for agents)

On Arista EOS devices with an S-BFD reflector proxy configured, a crafted S-BFD packet can make the device temporarily stop reflecting S-BFD packets. The result is S-BFD session timeouts, a disruption of link-liveness checks rather than code execution.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check whether the S-BFD reflector proxy is configured on the Arista EOS device; the sources do not name the exact command.
- Compare the running EOS version against the affected ranges in the Arista advisory; the sources do not list them.

## Timeline

- 2026-11-10T20:46:04+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-121294

## From the sources

On affected platforms running Arista EOS with a S-BFD reflector proxy configured, an unauthenticated attacker could send a crafted S-BFD Protocol Data Unit (PDU) that might cause the device to temporarily cease reflecting S-BFD packets, potentially resulting in S-BFD session timeouts.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_