CVE-2019-1804: Cisco Nexus 9000 Series Fabric Switches Application Centric Infrastructure Mode Default SSH Key Vulnerability

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-05-03 · updated 2026-06-17
Weakness: CWE-310

Description

A vulnerability in the SSH key management for the Cisco Nexus 9000 Series Application Centric Infrastructure (ACI) Mode Switch Software could allow an unauthenticated, remote attacker to connect to the affected system with the privileges of the root user. The vulnerability is due to the presence of a default SSH key pair that is present in all devices. An attacker could exploit this vulnerability by opening an SSH connection via IPv6 to a targeted device using the extracted key materials. An exploit could allow the attacker to access the system with the privileges of the root user. This vulnerability is only exploitable over IPv6; IPv4 is not vulnerable.

Affected products

Cisco Nexus 93108Tc-Ex Firmware: 14.0(3d)
Cisco Nexus 93120Tx Firmware: 14.0(3d)
Cisco Nexus 93128Tx Firmware: 14.0(3d)
Cisco Nexus 93180Yc-Ex Firmware: 14.0(3d)
Cisco Nexus 9332Pq Firmware: 14.0(3d)
Cisco Nexus 9372Px Firmware: 14.0(3d)
Cisco Nexus 9372Tx Firmware: 14.0(3d)
Cisco Nexus 9396Px Firmware: 14.0(3d)
Cisco Nexus 9396Tx Firmware: 14.0(3d)
Cisco Nexus 9500 Firmware: 14.0(3d)
Cisco Nexus 9504 Firmware: 14.0(3d)
Cisco Nexus 9508 Firmware: 14.0(3d)
Cisco Nexus 9516 Firmware: 14.0(3d)

References

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