FreeBSD : FreeBSD -- Resource exhaustion in TCP reassembly (0cb9d5bb-600a-11e6-a6c3-14dae9d210b8)

#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from the FreeBSD VuXML database :
#
# Copyright 2003-2018 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('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(92891);
  script_version("2.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/01/04");

  script_cve_id("CVE-2015-1417");
  script_xref(name:"FreeBSD", value:"SA-15:15.tcp");

  script_name(english:"FreeBSD : FreeBSD -- Resource exhaustion in TCP reassembly (0cb9d5bb-600a-11e6-a6c3-14dae9d210b8)");
  script_summary(english:"Checks for updated packages in pkg_info output");

  script_set_attribute(
    attribute:"synopsis", 
    value:
"The remote FreeBSD host is missing one or more security-related
updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"There is a mistake with the introduction of VNET, which converted the
global limit on the number of segments that could belong to reassembly
queues into a per-VNET limit. Because mbufs are allocated from a
global pool, in the presence of a sufficient number of VNETs, the
total number of mbufs attached to reassembly queues can grow to the
total number of mbufs in the system, at which point all network
traffic would cease. Impact : An attacker who can establish concurrent
TCP connections across a sufficient number of VNETs and manipulate the
inbound packet streams such that the maximum number of mbufs are
enqueued on each reassembly queue can cause mbuf cluster exhaustion on
the target system, resulting in a Denial of Service condition.

As the default per-VNET limit on the number of segments that can
belong to reassembly queues is 1/16 of the total number of mbuf
clusters in the system, only systems that have 16 or more VNET
instances are vulnerable."
  );
  # https://vuxml.freebsd.org/freebsd/0cb9d5bb-600a-11e6-a6c3-14dae9d210b8.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?45bba7aa"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:FreeBSD");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");

  script_set_attribute(attribute:"vuln_publication_date", value:"2015/07/28");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/08/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/08/12");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2021 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"FreeBSD Local Security Checks");

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

  exit(0);
}


include("audit.inc");
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);

flag = 0;

if (pkg_test(save_report:TRUE, pkg:"FreeBSD>=10.1<10.1_16")) flag++;
if (pkg_test(save_report:TRUE, pkg:"FreeBSD>=9.3<9.3_21")) flag++;
if (pkg_test(save_report:TRUE, pkg:"FreeBSD>=8.4<8.4_35")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:pkg_report_get());
  else security_warning(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");