Answer in brief
CVE-2026-20038 records a Medium severity (CVSS 5.8) vulnerability in Cisco Nexus 9000 Series Fabric Switches in ACI Mode Policy-Based Redirect Endpoint Group Contract Bypass Vulnerability. The current sources do not mark it as known exploited. The current feed maps Cisco/Cisco NX-OS System Software in ACI Mode (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 System Software in ACI Mode (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Cisco/Cisco NX-OS System Software in ACI Modegeneric | 15.2(1g) || 15.2(2e) || 15.2(2f) || 15.2(2g) || 15.2(2h) || 15.2(3f) || 15.2(3e) || 15.2(3g) || 15.2(4d) || 15.2(4e) || 15.2(5c) || 15.2(5d) || 16.0(1g) || 15.2(5e) || 15.2(4f) || 15.2(6e) || 15.2(6h) || 16.0(1j) || 15.2(6g) || 15.2(7f) || 15.2(7g) || 16.0(2h) || 15.2(8d) || 16.0(2j) || 15.2(8e) || 16.0(3d) || 16.0(3e) || 15.2(8f) || 15.2(8g) || 15.3(1d) || 15.2(8h) || 16.0(4c) || 15.3(2a) || 15.2(8i) || 16.0(5h) || 15.3(2b) || 16.0(3g) || 16.0(5j) || 15.3(2c) || 16.0(6c) || 15.3(2d) || 16.1(1f) || 16.0(7e) || 16.0(8e) || 15.3(2e) || 16.0(8f) || 16.1(2f) || 16.1(2g) || 15.3(2f) || 16.0(9c) || 16.1(3f) || 16.0(9d) || 16.0(6h) || 16.0(8h) || 16.1(3g) || 16.0(9e) || 16.1(4h) || 16.1(5e) || 16.2(1g) || 16.0(9f) || 16.2(2e) | 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 the endpoint group (EPG) contract functionality of Cisco Nexus 9000 Series Fabric Switches in ACI Mode could allow an unauthenticated, remote attacker to bypass configured EPG contracts. This vulnerability is due to an improper control with EPG contracts. An attacker could exploit this vulnerability by sending IPv4 or IPv6 packets using UDP source and destination ports that are assigned to DHCP traffic through an affected device. A successful exploit could allow the attacker to bypass EPG contracts on the affected device.
Quoted source text, attributed separately from HOL analysis.