Vulnerabilities > CVE-2016-2271 - Denial of Service vulnerability in XEN 4.6.0/4.6.1

#
# (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("compat.inc");

if (description)
{
  script_id(89013);
  script_version("2.4");
  script_cvs_date("Date: 2018/11/10 11:49:45");

  script_cve_id("CVE-2016-2271");

  script_name(english:"FreeBSD : xen-kernel -- VMX: guest user mode may crash guest with non-canonical RIP (81f9d6a4-ddaf-11e5-b2bd-002590263bf5)");
  script_summary(english:"Checks for updated package in pkg_info output");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote FreeBSD host is missing a security-related update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"The Xen Project reports :

VMX refuses attempts to enter a guest with an instruction pointer
which doesn't satisfy certain requirements. In particular, the
instruction pointer needs to be canonical when entering a guest
currently in 64-bit mode. This is the case even if the VM entry
information specifies an exception to be injected immediately (in
which case the bad instruction pointer would possibly never get used
for other than pushing onto the exception handler's stack). Provided
the guest OS allows user mode to map the virtual memory space
immediately below the canonical/non-canonical address boundary, a
non-canonical instruction pointer can result even from normal user
mode execution. VM entry failure, however, is fatal to the guest.

Malicious HVM guest user mode code may be able to crash the guest."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"http://xenbits.xen.org/xsa/advisory-170.html"
  );
  # https://vuxml.freebsd.org/freebsd/81f9d6a4-ddaf-11e5-b2bd-002590263bf5.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?1c59ccec"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:N/I:N/A:P");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/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:xen-kernel");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/02/17");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/02/28");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/02/29");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2018 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");

  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);


flag = 0;

if (pkg_test(save_report:TRUE, pkg:"xen-kernel<4.5.2_2")) flag++;

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

#%NASL_MIN_LEVEL 80502
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Fedora Security Advisory 2016-e48f4bd14f.
#

include("compat.inc");

if (description)
{
  script_id(89629);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");

  script_cve_id("CVE-2016-2270", "CVE-2016-2271");
  script_xref(name:"FEDORA", value:"2016-e48f4bd14f");

  script_name(english:"Fedora 23 : xen-4.5.2-8.fc23 (2016-e48f4bd14f)");
  script_summary(english:"Checks rpm output for the updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Fedora host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"x86: inconsistent cachability flags on guest mappings [XSA-154,
CVE-2016-2270] (#1309324) VMX: guest user mode may crash guest with
non-canonical RIP [XSA-170, CVE-2016-2271] (#1309323)

Note that Tenable Network Security has extracted the preceding
description block directly from the Fedora security advisory. Tenable
has attempted to automatically clean and format it as much as possible
without introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.redhat.com/show_bug.cgi?id=1304627"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.redhat.com/show_bug.cgi?id=1304628"
  );
  # https://lists.fedoraproject.org/pipermail/package-announce/2016-February/177990.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?f1b65ed1"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected xen package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:xen");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:23");

  script_set_attribute(attribute:"patch_publication_date", value:"2016/02/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/03/04");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2020 Tenable Network Security, Inc.");
  script_family(english:"Fedora Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/RedHat/release");
if (isnull(release) || "Fedora" >!< release) audit(AUDIT_OS_NOT, "Fedora");
os_ver = eregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora");
os_ver = os_ver[1];
if (! ereg(pattern:"^23([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 23.x", "Fedora " + os_ver);

if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu);

flag = 0;
if (rpm_check(release:"FC23", reference:"xen-4.5.2-8.fc23")) flag++;


if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "xen");
}

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Debian Security Advisory DSA-3519. The text 
# itself is copyright (C) Software in the Public Interest, Inc.
#

include("compat.inc");

if (description)
{
  script_id(90030);
  script_version("2.6");
  script_cvs_date("Date: 2018/11/10 11:49:37");

  script_cve_id("CVE-2015-8339", "CVE-2015-8340", "CVE-2015-8341", "CVE-2015-8550", "CVE-2015-8555", "CVE-2016-1570", "CVE-2016-1571", "CVE-2016-2270", "CVE-2016-2271");
  script_xref(name:"DSA", value:"3519");

  script_name(english:"Debian DSA-3519-1 : xen - security update");
  script_summary(english:"Checks dpkg output for the updated package");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Debian host is missing a security-related update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Multiple security issues have been found in the Xen virtualisation
solution, which may result in denial of service or information
disclosure.

The oldstable distribution (wheezy) will be updated in a separate DSA."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/jessie/xen"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://www.debian.org/security/2016/dsa-3519"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"Upgrade the xen packages.

For the stable distribution (jessie), these problems have been fixed
in version 4.4.1-9+deb8u4."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C");
  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:N/UI:N/S:C/C:H/I:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:xen");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:8.0");

  script_set_attribute(attribute:"patch_publication_date", value:"2016/03/17");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/03/21");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2018 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Debian Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Debian/release", "Host/Debian/dpkg-l");

  exit(0);
}


include("audit.inc");
include("debian_package.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Debian/release")) audit(AUDIT_OS_NOT, "Debian");
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;
if (deb_check(release:"8.0", prefix:"libxen-4.4", reference:"4.4.1-9+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"libxen-dev", reference:"4.4.1-9+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"libxenstore3.0", reference:"4.4.1-9+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"xen-hypervisor-4.4-amd64", reference:"4.4.1-9+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"xen-hypervisor-4.4-arm64", reference:"4.4.1-9+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"xen-hypervisor-4.4-armhf", reference:"4.4.1-9+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"xen-system-amd64", reference:"4.4.1-9+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"xen-system-arm64", reference:"4.4.1-9+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"xen-system-armhf", reference:"4.4.1-9+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"xen-utils-4.4", reference:"4.4.1-9+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"xen-utils-common", reference:"4.4.1-9+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"xenstore-utils", reference:"4.4.1-9+deb8u4")) flag++;

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