Symptom
A vulnerability in the 802.1X implementation for Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device.
The vulnerability is due to incomplete input validation of Extensible Authentication Protocol (EAP) over LAN (EAPOL) frames. An attacker could exploit this vulnerability by sending a crafted EAPOL frame to an interface on the targeted device. A successful exploit could allow the attacker to cause the Layer 2 (L2) forwarding process to restart multiple times, leading to a system-level restart of the device and a DoS condition.
Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
This advisory is available at the following link:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190306-nx-os-lan-auth
Conditions
Please refer to the Security Advisory.
Workaround
Please refer to the Security Advisory.
Further Problem Description
Please refer to the Security Advisory.
PSIRT Evaluation
The Cisco PSIRT has assigned this bug the following CVSS version 3 score. The Base CVSS score as of the time of evaluation is 7.4:
https://tools.cisco.com/security/center/cvssCalculator.x?version=3.0&vector=CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
CVE ID CVE-2019-1594 has been assigned to document this issue.
Additional information on Cisco''s security vulnerability policy can be found at the following URL:
http://www.cisco.com/en/US/products/products_security_vulnerability_policy.html
