# CVE-2026-73449: Security feature bypass in EOS

> An attacker can bypass RADIUS dynamic authorization to keep unauthorized 802.1X sessions active on Arista EOS devices with specific proxy configurations.

- **Severity:** Medium 5.9 (`CVSS:4.0/AV:A/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:L/SA:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Sep 2026
- **Updated:** 15 Sep 2026
- **Also known as:** GHSA-x95c-w9r9-rqxj

## What is CVE-2026-73449?

CVE-2026-73449 is a medium-severity vulnerability in Arista Networks EOS, published on 14 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

On affected platforms running Arista EOS with both 802.1X port authentication and the RADIUS proxy feature configured with dynamic authorization, a low-privileged attacker on an adjacent network segment who induces a RADIUS packet through a configured RADIUS proxy client can prevent RADIUS dynamic authorization messages, including Change-of-Authorization (CoA) and Disconnect-Requests as defined in RFC 5176, from being applied to locally authenticated 802.1X sessions.
This allows an endpoint session that a RADIUS server or network access control system has ordered disconnected to remain authorized on the network.
Both 802.1X port authentication with dynamic authorization and RADIUS proxy with dynamic authorization must be explicitly configured for a deployment to be exposed to this issue.
This issue was discovered internally by Arista, and the company is not aware of any malicious exploitation of this vulnerability in customer networks.

Weakness: CWE-290 (Authentication Bypass by Spoofing)

## Which versions are affected by CVE-2026-73449?


## How do I fix CVE-2026-73449?

No fix has been published for CVE-2026-73449 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-73449 being exploited?

There is no known exploitation of CVE-2026-73449 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-73449 and fix it if it is affected.

What it is: CVE-2026-73449 is a medium-severity vulnerability in Arista Networks EOS, published on 14 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-73449 in the wild and no public exploit code.

Affected product: Arista Networks EOS. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-73449/ (Markdown: https://insights.sbomify.com/CVE-2026-73449/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-73449
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-73449
- OSV: https://osv.dev/vulnerability/CVE-2026-73449

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-73449/
Summaries are generated and may contain mistakes; the official description above is the record.