FreeBSD : FreeBSD -- pf incorrectly matches different ICMPv6 states in the state table (f140cff0-771a-11ef-9a62-002590c1f29c)

high Nessus Plugin ID 207545

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Synopsis

The remote FreeBSD host is missing one or more security-related updates.

Description

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the f140cff0-771a-11ef-9a62-002590c1f29c advisory.

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.
This advisory introduced additional issues that were addressed by FreeBSD-EN-24:16.pf. Please refer to that erratum for additional fixes.

Tenable has extracted the preceding description block directly from the FreeBSD security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

https://www.freebsd.org/security/advisories/FreeBSD-EN-24:16.pf.asc

http://www.nessus.org/u?ee9adaeb

Plugin Details

Severity: High

ID: 207545

File Name: freebsd_pkg_f140cff0771a11ef9a62002590c1f29c.nasl

Version: 1.1

Type: local

Published: 9/21/2024

Updated: 9/21/2024

Configuration: Enable paranoid mode

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.4

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2024-6640

Vulnerability Information

CPE: p-cpe:/a:freebsd:freebsd:freebsd-kernel, cpe:/o:freebsd:freebsd

Required KB Items: Host/local_checks_enabled, Settings/ParanoidReport, Host/FreeBSD/release, Host/FreeBSD/pkg_info

Exploit Ease: No known exploits are available

Patch Publication Date: 9/20/2024

Vulnerability Publication Date: 8/11/2024

Reference Information

CVE: CVE-2024-6640

IAVA: 2024-A-0485-S