CyberSecBulletin
CVE-2026-7473Exploited in the wildNVD status: Analyzed

Arista Extensible Operating System Incomplete Comparison with Missing Factors

Published Updated By the CyberSecBulletin desk

CVE-2026-7473 is a medium-severity incomplete comparison with missing factors vulnerability in EOS from Arista Networks, with a CVSS 3.1 base score of 5.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected EOS versions: 4.36.0; 4.35.0 through 4.35; 4.34.0 through 4.34, and others listed below. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on June 9, 2026, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Check which version of EOS you run against the affected versions below, and install the vendor's latest release.
  2. CISA's 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.
  3. Read the advisory on arista.com for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Arista NetworksEOS4.36.0; 4.35.0 through 4.35; 4.34.0 through 4.34; 4.33.0 through 4.33; 4.32.0 through 4.32; 4.31.0 through 4.31; 4.30 and earlierNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
NoneNo data is disclosed.
Integrity
LowLimited modification of data is possible.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N. Scored by CNA (arista.com).

Scoring systemScoreSeverityScored by
CVSS 4.06.9MediumCNA (arista.com)
CVSS 3.15.8MediumCNA (arista.com)

Official description

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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Incomplete Comparison with Missing Factors

The product performs a comparison between entities that must consider multiple factors or characteristics of each entity, but the comparison does not include one or more of these factors.

More Incomplete Comparison with Missing Factors vulnerabilities (CWE-1023)

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: total).
  4. Deadline for US federal agencies to remediate, set by CISA.
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in EOS

All EOS vulnerabilities

Recent Incomplete Comparison with Missing Factors vulnerabilities

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