Medium severity · published Sep 16, 2026
CVE-2026-73450
On affected platforms running Arista EOS with MLAG Dual Primary Detection configured, an unauthenticated attacker with access to the Dual Primary Detection network segment can send specially crafted p
6.9
CVSS
0.2%
EPSS
No
On KEV
Description
On affected platforms running Arista EOS with MLAG Dual Primary Detection configured, an unauthenticated attacker with access to the Dual Primary Detection network segment can send specially crafted packets to interfere with the dual-primary state. If the MLAG primary switch fails while these packets are present, the secondary switch incorrectly concludes it is in a dual-primary condition and err-disables its interfaces, leading to a traffic interruption.
CVSS vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H
Attack vector
Adjacent
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 5% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EO
EOS · Arista Networks
4.36.0 through 4.36.1F; 4.35.0 through 4.35.5M; 4.34.0 through 4.34.7.1M; 4.33.0 through 4.33.9M; 0.0.0 before 4.33.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-73450
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-73450
www.arista.com
https://www.arista.com/en/support/advisories-notices/security-advisory/24717-security-advisory-0161
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