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CVE-2024-6640

pf incorrectly matches different ICMPv6 states in the state table PUBLISHED

Description (CNA)

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.

Affected (CNA)

Vendor / productVersions
FreeBSD / FreeBSDaffected 14.1-RELEASE before p3; affected 14.0-RELEASE before p9; affected 13.3-RELEASE before p5

CWE

No CWE identifiers supplied.

References

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.

CVE

No English description supplied.