CVE-2026-20038
Cisco Nexus 9000 Series Fabric Switches in ACI Mode Policy-Based Redirect Endpoint Group Contract Bypass Vulnerability
Description
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.
Weakness: CWE-284
Affected products
| Vendor | Product | Category | Matched by |
|---|---|---|---|
| Cisco | Cisco NX-OS Software | Routing & Switching | cna-assigner |
Vendor-reported products (1)
- Cisco · Cisco NX-OS System Software in ACI Mode
Vendor advisory
Cisco Nexus 9000 Series Fabric Switches in ACI Mode Endpoint Group Contract Bypass Vulnerability
Cisco’s rating: Medium (advisory CVSS 5.8) · Published Oct 7, 2026
Bug ID: CSCwr18270
The vendor’s rating applies to the whole advisory and can differ from this CVE’s own CVSS severity. Where this comes from