CVE-2026-73459

On affected platforms running Arista EOS with IS-IS configured, an unauthenticated attacker who can inject a specially crafted IS-IS LSP PDU can cause the legitimate LSP to be unexpectedly purged from the IS-IS link-state database. This may result in traffic loss.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.0

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://www.arista.com/en/support/advisories-notices/security-advisory/24716-security-advisory-0160

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-16 00:17

Updated : 2026-09-16 00:17

NVD link : CVE-2026-73459

Mitre link : CVE-2026-73459

CVE.ORG link : CVE-2026-73459

JSON object : View

Products Affected

No product.

CWE

CWE-354

Improper Validation of Integrity Check Value

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