Known exploited · Arista
CVE-2026-7473: Arista Extensible Operating System Incomplete Comparison with Missing Factors Vulnerability
What it is
Arista Extensible Operating System (EOS) contains an incomplete comparison with missing factors vulnerability when the switch incorrectly decapsulate and forwards other unexpected tunneled packet with a destination IP matching its configured decapsulation IP.
- Vendor
- Arista
- Product
- Extensible Operating System
- Added to KEV
- June 9, 2026
- CISA due date
- June 23, 2026
- Ransomware use
- Unknown
What CISA requires
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Forensic triage
No
What to do now
- Find every instance of Extensible Operating System you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before June 23, 2026 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.