Symptom
A vulnerability in the Cisco Fabric Services (CFS) component of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause process crashes, which can result in a denial of service (DoS) condition on an affected system.
The vulnerability is due to insufficient validation of TCP packets when processed by the Cisco Fabric Services over IP (CFSoIP) feature. An attacker could exploit this vulnerability by sending a crafted CFS TCP packet to an affected device. A successful exploit could allow the attacker to cause process crashes, resulting in a device reload and a DoS condition.
Note: There are three distribution methods that can be configured for CFS. This vulnerability only affects distribution method CFSoIP, which is disabled by default. See the Security Advisory for more information.
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-20190828-nxos-fsip-dos
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 8.6:
https://tools.cisco.com/security/center/cvssCalculator.x?version=3.0&vector=CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
CVE ID CVE-2019-1962 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
