FreeBSD : FreeBSD -- NFS client data corruption and kernel memory disclosure (8eefff69-997f-11ee-8e38-002590c1f29c)

#%NASL_MIN_LEVEL 80900
#
# (C) Tenable, Inc.
#
# @NOAGENT@
#
# The descriptive text and package checks in this plugin were
# extracted from the FreeBSD VuXML database :
#
# Copyright 2003-2021 Jacques Vidrine and contributors
#
# Redistribution and use in source (VuXML) and 'compiled' forms (SGML,
# HTML, PDF, PostScript, RTF and so forth) with or without modification,
# are permitted provided that the following conditions are met:
# 1. Redistributions of source code (VuXML) must retain the above
#    copyright notice, this list of conditions and the following
#    disclaimer as the first lines of this file unmodified.
# 2. Redistributions in compiled form (transformed to other DTDs,
#    published online in any format, converted to PDF, PostScript,
#    RTF and other formats) must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer
#    in the documentation and/or other materials provided with the
#    distribution.
#
# THIS DOCUMENTATION IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
# OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
# OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
# BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
# OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION,
# EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#

include('compat.inc');

if (description)
{
  script_id(186807);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/12/21");

  script_cve_id("CVE-2023-6660");

  script_name(english:"FreeBSD : FreeBSD -- NFS client data corruption and kernel memory disclosure (8eefff69-997f-11ee-8e38-002590c1f29c)");

  script_set_attribute(attribute:"synopsis", value:
"The remote FreeBSD host is missing one or more security-related updates.");
  script_set_attribute(attribute:"description", value:
"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 8eefff69-997f-11ee-8e38-002590c1f29c advisory.

  - In FreeBSD 13.2 and 14.0, the NFS client was optimized to improve         the performance of IO_APPEND
    writes, that is, writes which add data         to the end of a file and so extend its size.  This
    uncovered an old         bug in some routines which copy userspace data into the kernel.         The bug
    also affects the NFS client's implementation of direct I/O;         however, this implementation is
    disabled by default by the         vfs.nfs.nfs_directio_enable sysctl and is only used to handle
    synchronous writes. When a program running on an affected system appends data to a         file via an NFS
    client mount, the bug can cause the NFS client to         fail to copy in the data to be written but
    proceed as though the         copy operation had succeeded.  This means that the data to be written
    is instead replaced with whatever data had been in the packet buffer         previously.  Thus, an
    unprivileged user with access to an affected         system may abuse the bug to trigger disclosure of
    sensitive         information.  In particular, the leak is limited to data previously         stored in
    mbufs, which are used for network transmission and         reception, and for certain types of inter-
    process communication. The bug can also be triggered unintentionally by system         applications, in
    which case the data written by the application to an         NFS mount may be corrupted.  Corrupted data
    is written over the         network to the NFS server, and thus also susceptible to being snooped
    by other hosts on the network. Note that the bug exists only in the NFS client; the version and
    implementation of the server has no effect on whether a given system         is affected by the problem.
    (CVE-2023-6660)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  # https://vuxml.freebsd.org/freebsd/8eefff69-997f-11ee-8e38-002590c1f29c.html
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?69dbeb3d");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:C/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2023-6660");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2023/12/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2023/12/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/12/13");

  script_set_attribute(attribute:"potential_vulnerability", value:"true");
  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:FreeBSD-kernel");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"FreeBSD Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2023 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Settings/ParanoidReport", "Host/local_checks_enabled", "Host/FreeBSD/release", "Host/FreeBSD/pkg_info");

  exit(0);
}


include("freebsd_package.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/FreeBSD/release")) audit(AUDIT_OS_NOT, "FreeBSD");
if (!get_kb_item("Host/FreeBSD/pkg_info")) audit(AUDIT_PACKAGE_LIST_MISSING);

if (report_paranoia < 2) audit(AUDIT_PARANOID);

var flag = 0;

var packages = [
    'FreeBSD>=13.2<13.2_8',
    'FreeBSD>=14.0<14.0_3'
];

foreach var package( packages ) {
    if (pkg_test(save_report:TRUE, pkg: package)) flag++;
}

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : pkg_report_get()
  );
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");