Denial of Service Vulnerability in Cisco NX-OS Software
CVE-2026-20173

5.8MEDIUM

Key Information:

Vendor

Cisco
Status
Cisco Nx-os Software
Vendor
CVE Published:
7 October 2026

Badges

👾 Exploit Exists

What is CVE-2026-20173?

A vulnerability in Cisco NX-OS Software allows unauthenticated remote attackers to exploit the system by sending a surge of UDP or TCP connections to a data plane interface. This flaw arises from improper rate limiting on certain protocols, enabling attackers to destabilize routing and control plane protocols, leading to system instability and potential denial of service. Fortunately, the disruption subsides without manual intervention once the excessive traffic ceases.

Affected Version(s)

Cisco NX-OS Software 8.2(5)

Cisco NX-OS Software 7.3(5)D1(1)

Cisco NX-OS Software 8.4(2)

References

https://sec.cloudapps.cisco.com/security/center/content/C...

CVSS V3.1

Score:
5.8
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Changed

Timeline

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

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