CVE-2026-7473Arista EOS Unexpected Tunnel Protocol Decapsulation and Forwarding Bypass
Updated under an hour ago ()
Does this affect you?
It affects Arista Networks EOS and 1 other product. Add what you run to find out whether that includes you.
CISA lists it as known exploited since Jun 9, 2026; federal agencies had to remediate by Jun 23, 2026. Treat that date as your deadline.
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Free account, 1 product
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.
- CVSS
- 5.8 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
- Weakness (CWE)
- CWE-1023
- Known exploited
- Added to CISA KEV Jun 9, 2026; federal remediation due Jun 23, 2026Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- EPSS (exploitation in the next 30 days)
- 0.65% (percentile 50)
- Assigned by
- Arista
- NVD analysis
- Analyzed
- Record last updated
- Oct 7, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Arista Networks EOS arista_networks:eos (from the name) | 4.36.0; from 4.35.0 through 4.35; from 4.34.0 through 4.34; from 4.33.0 through 4.33; from 4.32.0 through 4.32; from 4.31.0 through 4.31; through 4.30 | CNA record |
arista eos arista:eos | all versions | NVD |
References
- https://www.arista.com/en/support/advisories-notices/security-advisory/22872-security-advisory-0137vendor-advisory, broken-link
- https://www.arista.com/en/support/advisories-notices/security-advisory/24005-security-advisory-0137mitigation, vendor-advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-7473us-government-resource
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.