Cisco Firepower Threat Defense Software and Cisco FirePOWER Services ICMPv6 with Snort 2 Denial of Service Vulnerability

A vulnerability in ICMPv6 inspection when configured with the Snort 2 detection engine for Cisco Firepower Threat Defense (FTD) Software or Cisco FirePOWER Services could allow an unauthenticated, remote attacker to cause the CPU of an affected device to spike to 100 percent, which could stop all traffic processing and result in a denial of service (DoS) condition. FTD management traffic is not affected by this vulnerability.

This vulnerability is due to improper error checking when parsing fields within the ICMPv6 header. An attacker could exploit this vulnerability by sending a crafted ICMPv6 packet through an affected device. A successful exploit could allow the attacker to cause the device to exhaust CPU resources and stop processing traffic, resulting in a DoS condition.

Note: To recover from the DoS condition, the Snort 2 Detection Engine, the Cisco FTD device, or the Cisco FirePOWER Services device may need to be restarted. For more information, see the Details [“#details”] section of this advisory.

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-ftd-icmpv6-dos-4eMkLuN [“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-icmpv6-dos-4eMkLuN”]

This advisory is part of the November 2023 release of the Cisco ASA, FTD, and FMC Security Advisory Bundled publication. For a complete list of the advisories and links to them, see Cisco Event Response: November 2023 Semiannual Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication [“https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74985”].