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.
History

Tue, 26 Nov 2024 15:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-276
Metrics cvssV3_1

{'score': 6.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 16 Aug 2024 17:30:00 +0000

Type Values Removed Values Added
References
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 13 Aug 2024 19:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Sun, 11 Aug 2024 03:00:00 +0000

Type Values Removed Values 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.
Title pf incorrectly matches different ICMPv6 states in the state table
References

cve-icon MITRE

Status: PUBLISHED

Assigner: freebsd

Published: 2024-08-11T02:33:42.590Z

Updated: 2024-11-26T15:05:41.535Z

Reserved: 2024-07-10T00:40:14.138Z

Link: CVE-2024-6640

cve-icon Vulnrichment

Updated: 2024-08-16T17:02:44.316Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2024-08-12T13:38:39.380

Modified: 2024-11-26T15:15:35.053

Link: CVE-2024-6640

cve-icon Redhat

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