Answer in brief
CVE-2026-20173 records a Medium severity (CVSS 5.8) vulnerability in Cisco NX-OS Software Denial of Service Vulnerability. The current sources do not mark it as known exploited. The current feed maps Cisco/Cisco NX-OS Software (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Cisco/Cisco NX-OS Software (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Cisco/Cisco NX-OS Softwaregeneric | 8.2(5) || 7.3(5)D1(1) || 8.4(2) || 8.4(3) || 9.2(3) || 9.2(2v) || 7.3(4)D1(1) || 8.2(1) || 9.2(1) || 9.2(2t) || 9.2(3y) || 9.3(2) || 8.1(1) || 8.2(2) || 8.3(2) || 7.3(2)D1(3a) || 9.2(4) || 8.1(2) || 7.3(3)D1(1) || 8.2(3) || 8.4(1) || 7.3(0)DX(1) || 7.3(2)D1(1) || 9.3(1) || 7.3(2)D1(2) || 8.2(4) || 9.3(1z) || 9.2(2) || 8.1(2a) || 7.3(2)D1(3) || 8.3(1) || 7.3(1)D1(1) || 7.3(0)D1(1) || 9.3(3) || 7.3(2)D1(1d) || 9.3(4) || 7.3(6)D1(1) || 8.2(6) || 9.3(5) || 9.3(6) || 8.4(4) || 7.3(7)D1(1) || 9.3(5w) || 8.2(7) || 9.3(7) || 9.3(7k) || 7.3(8)D1(1) || 9.3(7a) || 8.2(7a) || 9.3(8) || 8.4(4a) || 8.4(5) || 8.2(8) || 9.3(9) || 7.3(9)D1(1) || 8.4(6) || 9.3(10) || 8.2(9) || 10.3(1) || 8.4(7) || 10.3(2) || 8.4(6a) || 9.3(11) || 10.3(3) || 8.2(10) || 9.3(12) || 10.4(1) || 8.4(8) || 10.3(99w) || 10.3(3w) || 10.3(99x) || 10.3(3o) || 8.4(9) || 10.3(4) || 10.3(3p) || 10.3(4a) || 10.4(2) || 10.3(3q) || 9.3(13) || 8.2(11) || 10.3(5) || 10.4(3) || 10.3(3x) || 10.3(4g) || 10.5(1) || 8.4(10) || 10.3(3r) || 10.3(6) || 9.3(14) || 10.4(4) || 10.3(4h) || 10.5(2) || 8.4(11) || 10.3(7) || 10.4(5) || 10.5(3) || 9.3(15) || 10.4(4g) || 10.5(4) || 8.4(12) || 10.5(3t) || 10.3(8) || 10.4(6) || 10.5(3s) || 10.5(3e) || 10.5(3o) || 9.3(16) || 10.5(3p) || 10.4(7) || 10.5(5) || 9.3(17) | Not reported |
Published upstream
Oct 7, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 7, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 7, 2026
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.
Quoted source text, attributed separately from HOL analysis.