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Medium · 5.8 Known exploited Public exploit CVE-2026-7473 EUVD-2026-34858GHSA-mcx4-vm6v-r473

Arista EOS Unexpected Tunnel Protocol Decapsulation and Forwarding Bypass

Published Jun 5, 2026 · Updated Oct 7, 2026 · Assigned by Arista

Vendor: Arista Networks Product: EOS Category: Network devices

Description

On affected platforms running Arista EOS where a tunnel decapsulation configuration—such as VXLAN (Virtual Extensible LAN), decap-groups, or a GRE (Generic Routing Encapsulation) tunnel interface—is present, the switch will incorrectly decapsulate and forward other unexpected tunneled packet with a destination IP matching its configured decapsulation IP. This occurs because the switch does not verify the tunnel protocol type, potentially leading to the unexpected processing of non-configured tunnel traffic.

This issue has been reported as being exploited in the wild.

Affected products

VendorProductAffectedFixed
Arista Networks EOS 4.36.0, 4.35.0 – ≤ 4.35, 4.34.0 – ≤ 4.34, 4.33.0 – ≤ 4.33, 4.32.0 – ≤ 4.32, 4.31.0 – ≤ 4.31, ≤ 4.30 —

Public exploits

Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.

Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.

GitHub 1 repository

Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.

Advisories 1

References