Arista Extensible Operating System
CVE-2026-7473
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.
What this means for your business
- It affects Arista Extensible Operating System. It matters if your company, or a supplier that handles your data, runs it.
- Attackers are already using it. CISA added it to its list of flaws used in real attacks on 9 June 2026.
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 1% chance of attack attempts being seen in the next 30 days, ranking above 65% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Arista Extensible Operating System, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
- 3Treat it as urgent. US federal agencies must fix it by 23 June 2026. That deadline does not apply to private companies, but it shows how seriously CISA takes it.
- 4Because attackers have used it, check the affected systems for signs of a break-in, not only for the update.
Fastnexa security experts
Attackers are already using this flaw. Is your Arista Extensible Operating System exposed?
Tell us where you run Arista Extensible Operating System and a Fastnexa penetration tester will check whether this flaw, or others like it, can be used against your websites, apps and network.
The full test is free for our first 10 founding clients until 31 December 2026. See the offer
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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.
CISA’s wording, unedited.
Scoring
- CVSS
- 5.8 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N- CVSS v4
- 6.9
- Weakness
- CWE-1023
- Assigned by
- psirt@arista.com
Dates
- Published
- 2026-06-09
- Last modified
- 2026-10-07
- Added to KEV
- 2026-06-09
- Remediation due
- 2026-06-23
- Sources
- CISA KEV, NVD
Affected products
- Arista Eosall versions
- Arista 7020sr-24c2all versions
- Arista 7020sr-32c2all versions
- Arista 7020srg-24c2all versions
- Arista 7020tr-48all versions
- Arista 7020tra-48all versions
- Arista 7280cr-48all versions
- Arista 7280cr2-60all versions
- Arista 7280cr2a-30all versions
- Arista 7280cr2a-60all versions
- Arista 7280cr2k-30all versions
- Arista 7280cr2k-60all versions
As listed in the NVD configuration data. Not a statement about your estate.