U.S. flag   An official website of the United States government
Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock (Dot gov) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database

Vulnerability Change Records for CVE-2024-6640

Change History

New CVE Received from FreeBSD 8/12/2024 9:38:39 AM

Action Type Old Value New Value
Added Description 

								
							
							
								
							
						
								
							
								
In ICMPv6 Neighbor Discovery (ND), the ID is always 0.  When pf is configured to allow ND and block incoming Echo Requests, a crafted Echo Request packet after a Neighbor Solicitation (NS) can trigger an Echo Reply.  The packet has to come from the same host as the NS and have a zero as identifier to match the state created by the Neighbor Discovery and allow replies to be generated.

ICMPv6 packets with identifier value of zero bypass firewall rules written on the assumption that the incoming packets are going to create a state in the state table.

								
								
					

					

						Added
						Reference
						
							
							
								
							
								

								
							
							
								
							
						
								
							
								
FreeBSD https://security.freebsd.org/advisories/FreeBSD-SA-24:05.pf.asc [No types assigned]