Cisco Nexus 9000 Series ACI Mode Switch Software Link Layer Discovery Protocol Buffer Overflow Vulnerability

A vulnerability in the Link Layer Discovery Protocol (LLDP) subsystem of Cisco Nexus 9000 Series Application Centric Infrastructure (ACI) Mode Switch Software could allow an adjacent, unauthenticated attacker to cause a denial of service (DoS) condition or execute arbitrary code with root privileges.

The vulnerability is due to improper input validation of certain type, length, value (TLV) fields of the LLDP frame header. An attacker could exploit this vulnerability by sending a crafted LLDP packet to the targeted device. A successful exploit may lead to a buffer overflow condition that could either cause a DoS condition or allow the attacker to execute arbitrary code with root privileges.

Note: This vulnerability cannot be exploited by transit traffic through the device; the crafted packet must be targeted to a directly connected interface. In addition, the attack surface for this vulnerability can be greatly reduced by disabling LLDP on interfaces where it is not required.

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-20190731-nxos-bo [“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190731-nxos-bo”]