CVE-2026-7473 — Arista EOS Unexpected Tunnel Protocol Decapsulation and Forwarding Bypass

Description (CNA)

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 (CNA)

Vendor / product	Versions
Arista Networks / EOS	affected 4.36.0; affected 4.35.0 through 4.35; affected 4.34.0 through 4.34; affected 4.33.0 through 4.33; affected 4.32.0 through 4.32; affected 4.31.0 through 4.31; affected * through 4.30

CWE

CWE-1023

References

https://www.arista.com/en/support/advisories-notices/security-advisory/22872-security-advisory-0137

ADP enrichment

CISA-ADP

No English description supplied.