Cisco FXOS and NX-OS Software Authenticated Simple Network Management Protocol Denial of Service Vulnerability

A vulnerability in the Simple Network Management Protocol (SNMP) input packet processor of Cisco FXOS Software and Cisco NX-OS Software could allow an authenticated, remote attacker to cause the SNMP application on an affected device to restart unexpectedly.

The vulnerability is due to improper validation of Abstract Syntax Notation One (ASN.1)-encoded variables in SNMP packets. An attacker could exploit this vulnerability by sending a crafted SNMP packet to the SNMP daemon on the affected device. A successful exploit could allow the attacker to cause the SNMP application to restart multiple times, leading to a system-level restart and a denial of service (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://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-fxnxos-snmp-dos [“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190828-fxnxos-snmp-dos”]
This advisory is part of the August 2019 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication, which includes five Cisco Security Advisories that describe five vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: August 2019 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication [“https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-72243”].