CVE-2026-7473: Arista Extensible Operating System Incomplete Comparison with Missing Factors Vulnerability
Arista · Extensible Operating System · NVD published 2026-06-05 · posted 2026-06-09 · last modified 2026-10-08
What it is
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.
| Weakness | CWE-1023 |
|---|---|
| CVSS vector | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X (source: [email protected]) |
| CISA due date | 2026-06-23 (for US federal agencies under BOD; a good deadline for everyone) |
| ATT&CK tactics | n/a |
Exploitation evidence
First exploit evidence seen: 2026-06-09 (earliest date across the sources below).
Exploited in the wild
- CISA KEV: listed since 2026-06-09. Source
Public exploit code
GitHub proof-of-concept repositories below quality bar
1 public repositories from 1 accounts, first seen 2026-06-10.
Verify before running: public PoCs can be malicious. Read the code and only run it in an isolated lab. A PoC means exploit code is public, not that this CVE is exploited in the wild.
Sources: CISA KEV · nomi-sec/PoC-in-GitHub.
No ATT&CK techniques could be mapped or inferred for this CVE yet.
How to fix it
CISA required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. (source: CISA KEV)
Fixed versions
NVD does not list a fixed version for this CVE. Use the vendor advisory below.
Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.
Vendor advisories and patches
- https://www.arista.com/en/support/advisories-notices/security-advisory/24005-security-advisory-0137 (CISA KEV notes)
Detection Generic guidance
Response checklist Generic guidance
- Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
- Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
- Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
- Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.
Sources
- NVD: CVE-2026-7473
- CVE.org record
- CISA Known Exploited Vulnerabilities catalog
- FIRST EPSS (2026-10-24)
- https://www.arista.com/en/support/advisories-notices/security-advisory/22872-security-advisory-0137 (Broken Link)
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-7473 (US Government Resource)