Vulnerability in Arista EOS IS-IS Graceful Restart Mechanism
CVE-2026-73460

7HIGH

Key Information:

Vendor

Arista Networks

Status
Eos
Vendor
CVE Published:
15 September 2026

What is CVE-2026-73460?

On platforms running Arista EOS with IS-IS graceful restart enabled, an unauthenticated attacker can exploit this vulnerability by injecting a malformed IS-IS LSP PDU packet. This malicious action leads to the premature termination of the graceful restart procedure, which could result in significant traffic disruption following a restart event, impacting overall network performance.

Affected Version(s)

EOS 4.36.0 <= 4.36.1F

References

https://www.arista.com/en/support/advisories-notices/secu...
vendor-advisory

CVSS V4

Score:
7
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Adjacent Network
Attack Complexity:
High
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

This issue was discovered internally by Arista and the company is not aware of any malicious uses of these issues in customer networks.
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