Cisco IOS and IOS XE Software PROFINET Link Layer Discovery Protocol Denial of Service Vulnerability

A vulnerability in the PROFINET handler for Link Layer Discovery Protocol (LLDP) messages of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a crash on an affected device, resulting in a denial of service (DoS) condition.

The vulnerability is due to insufficient validation of LLDP messages in the PROFINET LLDP message handler. An attacker could exploit this vulnerability by sending a malicious LLDP message to an affected device. A successful exploit could allow the attacker to cause the affected device to reload.

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-ios-profinet-dos-65qYG3W5 [“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-profinet-dos-65qYG3W5”]

A companion advisory for affected devices that support PROFINET is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-profinet-J9QMCHPB [“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-profinet-J9QMCHPB”].

This advisory is part of the September 24, 2020, release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication, which includes 25 Cisco Security Advisories that describe 34 vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: September 2020 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication [“https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74268”].