CVE-2026-20173

A vulnerability in Cisco NX-OS Software could allow an unauthenticated, remote attacker to exhaust system resources, causing a denial of service (DoS) condition. This vulnerability exists because rate limiting was improperly applied to some protocols. An attacker could exploit this vulnerability by sending a high rate of UDP or TCP connections to a data plane interface on an affected device. A successful exploit could allow the attacker to cause instability to various routing and control plane protocols through some packet loss and temporary disruptions, causing a DoS condition. This DoS condition will clear without manual intervention soon after the high rate of traffic is stopped.

CVSS v3 5.8 MEDIUM

5.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope CHANGED

References

Link	Resource
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-nscpdos-SnderkC7

Configurations

No configuration.

History

07 Oct 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-07 17:16

Updated : 2026-10-08 20:08

NVD link : CVE-2026-20173

Mitre link : CVE-2026-20173

CVE.ORG link : CVE-2026-20173

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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{"status": "affected", "version": "7.3(5)D1(1)"}, {"status": "affected", "version": "8.4(2)"}, {"status": "affected", "version": "8.4(3)"}, {"status": "affected", "version": "9.2(3)"}, {"status": "affected", "version": "9.2(2v)"}, {"status": "affected", "version": "7.3(4)D1(1)"}, {"status": "affected", "version": "8.2(1)"}, {"status": "affected", "version": "9.2(1)"}, {"status": "affected", "version": "9.2(2t)"}, {"status": "affected", "version": "9.2(3y)"}, {"status": "affected", "version": "9.3(2)"}, {"status": "affected", "version": "8.1(1)"}, {"status": "affected", "version": "8.2(2)"}, {"status": "affected", "version": "8.3(2)"}, {"status": "affected", "version": "7.3(2)D1(3a)"}, {"status": "affected", "version": "9.2(4)"}, {"status": "affected", "version": "8.1(2)"}, {"status": "affected", "version": "7.3(3)D1(1)"}, {"status": "affected", "version": "8.2(3)"}, {"status": "affected", "version": "8.4(1)"}, {"status": "affected", "version": "7.3(0)DX(1)"}, {"status": "affected", 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"8.2(7)"}, {"status": "affected", "version": "9.3(7)"}, {"status": "affected", "version": "9.3(7k)"}, {"status": "affected", "version": "7.3(8)D1(1)"}, {"status": "affected", "version": "9.3(7a)"}, {"status": "affected", "version": "8.2(7a)"}, {"status": "affected", "version": "9.3(8)"}, {"status": "affected", "version": "8.4(4a)"}, {"status": "affected", "version": "8.4(5)"}, {"status": "affected", "version": "8.2(8)"}, {"status": "affected", "version": "9.3(9)"}, {"status": "affected", "version": "7.3(9)D1(1)"}, {"status": "affected", "version": "8.4(6)"}, {"status": "affected", "version": "9.3(10)"}, {"status": "affected", "version": "8.2(9)"}, {"status": "affected", "version": "10.3(1)"}, {"status": "affected", "version": "8.4(7)"}, {"status": "affected", "version": "10.3(2)"}, {"status": "affected", "version": "8.4(6a)"}, {"status": "affected", "version": "9.3(11)"}, {"status": "affected", "version": "10.3(3)"}, {"status": "affected", "version": "8.2(10)"}, {"status": "affected", "version": "9.3(12)"}, {"status": "affected", "version": "10.4(1)"}, {"status": "affected", "version": "8.4(8)"}, {"status": "affected", "version": "10.3(99w)"}, {"status": "affected", "version": "10.3(3w)"}, {"status": "affected", "version": "10.3(99x)"}, {"status": "affected", "version": "10.3(3o)"}, {"status": "affected", "version": "8.4(9)"}, {"status": "affected", "version": "10.3(4)"}, {"status": "affected", "version": "10.3(3p)"}, {"status": "affected", "version": "10.3(4a)"}, {"status": "affected", "version": "10.4(2)"}, {"status": "affected", "version": "10.3(3q)"}, {"status": "affected", "version": "9.3(13)"}, {"status": "affected", "version": "8.2(11)"}, {"status": "affected", "version": "10.3(5)"}, {"status": "affected", "version": "10.4(3)"}, {"status": "affected", "version": "10.3(3x)"}, {"status": "affected", "version": "10.3(4g)"}, {"status": "affected", "version": "10.5(1)"}, {"status": "affected", "version": "8.4(10)"}, {"status": "affected", "version": "10.3(3r)"}, {"status": "affected", "version": "10.3(6)"}, {"status": "affected", "version": "9.3(14)"}, {"status": "affected", "version": "10.4(4)"}, {"status": "affected", "version": "10.3(4h)"}, {"status": "affected", "version": "10.5(2)"}, {"status": "affected", "version": "8.4(11)"}, {"status": "affected", "version": "10.3(7)"}, {"status": "affected", "version": "10.4(5)"}, {"status": "affected", "version": "10.5(3)"}, {"status": "affected", "version": "9.3(15)"}, {"status": "affected", "version": "10.4(4g)"}, {"status": "affected", "version": "10.5(4)"}, {"status": "affected", "version": "8.4(12)"}, {"status": "affected", "version": "10.5(3t)"}, {"status": "affected", "version": "10.3(8)"}, {"status": "affected", "version": "10.4(6)"}, {"status": "affected", "version": "10.5(3s)"}, {"status": "affected", "version": "10.5(3e)"}, {"status": "affected", "version": "10.5(3o)"}, {"status": "affected", "version": "9.3(16)"}, {"status": "affected", "version": "10.5(3p)"}, {"status": "affected", "version": "10.4(7)"}, {"status": "affected", "version": "10.5(5)"}, {"status": "affected", "version": "9.3(17)"}], "defaultStatus": "unknown"}]}], "published": "2026-10-07T17:16:54.843", "references": [{"url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-nscpdos-SnderkC7", "source": "psirt@cisco.com"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "psirt@cisco.com", "description": [{"lang": "en", "value": "CWE-770"}]}], "descriptions": [{"lang": "en", "value": "A vulnerability in Cisco NX-OS Software could allow an unauthenticated, remote attacker to exhaust system resources, causing a denial of service (DoS) condition.\r\n\r\nThis vulnerability exists because rate limiting was improperly applied to some protocols. An attacker could exploit this vulnerability by sending a high rate of UDP or TCP connections to a data plane interface on an affected device. A successful exploit could allow the attacker to cause instability to various routing and control plane protocols through some packet loss and temporary disruptions, causing a DoS condition. This DoS condition will clear without manual intervention soon after the high rate of traffic is stopped."}], "lastModified": "2026-10-08T20:08:45.857", "sourceIdentifier": "psirt@cisco.com"}