Ubuntu 17.04 : linux, linux-raspi2 vulnerability (USN-3484-1)

2017-11-21T00:00:00
ID UBUNTU_USN-3484-1.NASL
Type nessus
Reporter Ubuntu Security Notice (C) 2017-2019 Canonical, Inc. / NASL script (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
Modified 2020-10-02T00:00:00

Description

It was discovered that the KVM subsystem in the Linux kernel did not properly keep track of nested levels in guest page tables. A local attacker in a guest VM could use this to cause a denial of service (host OS crash) or possibly execute arbitrary code in the host OS.

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-3484-1. The text 
# itself is copyright (C) Canonical, Inc. See 
# <http://www.ubuntu.com/usn/>. Ubuntu(R) is a registered 
# trademark of Canonical, Inc.
#

include("compat.inc");

if (description)
{
  script_id(104714);
  script_version("3.8");
  script_cvs_date("Date: 2019/09/18 12:31:47");

  script_cve_id("CVE-2017-12188");
  script_xref(name:"USN", value:"3484-1");

  script_name(english:"Ubuntu 17.04 : linux, linux-raspi2 vulnerability (USN-3484-1)");
  script_summary(english:"Checks dpkg output for updated packages.");

  script_set_attribute(
    attribute:"synopsis", 
    value:
"The remote Ubuntu host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"It was discovered that the KVM subsystem in the Linux kernel did not
properly keep track of nested levels in guest page tables. A local
attacker in a guest VM could use this to cause a denial of service
(host OS crash) or possibly execute arbitrary code in the host OS.

Note that Tenable Network Security has extracted the preceding
description block directly from the Ubuntu 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://usn.ubuntu.com/3484-1/"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H");
  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:canonical:ubuntu_linux:linux-image-4.10-generic");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.10-generic-lpae");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.10-lowlatency");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.10-raspi2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-generic");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi2");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:17.04");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/10/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/11/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/11/21");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2017-2019 Canonical, Inc. / NASL script (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Ubuntu Local Security Checks");

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

  exit(0);
}


include("audit.inc");
include("ubuntu.inc");
include("ksplice.inc");

if ( ! get_kb_item("Host/local_checks_enabled") ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/Ubuntu/release");
if ( isnull(release) ) audit(AUDIT_OS_NOT, "Ubuntu");
release = chomp(release);
if (! preg(pattern:"^(17\.04)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 17.04", "Ubuntu " + release);
if ( ! get_kb_item("Host/Debian/dpkg-l") ) 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, "Ubuntu", cpu);

if (get_one_kb_item("Host/ksplice/kernel-cves"))
{
  rm_kb_item(name:"Host/uptrack-uname-r");
  cve_list = make_list("CVE-2017-12188");
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "KSplice hotfix for USN-3484-1");
  }
  else
  {
    _ubuntu_report = ksplice_reporting_text();
  }
}

flag = 0;

if (ubuntu_check(osver:"17.04", pkgname:"linux-image-4.10.0-1021-raspi2", pkgver:"4.10.0-1021.24")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"linux-image-4.10.0-40-generic", pkgver:"4.10.0-40.44")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"linux-image-4.10.0-40-generic-lpae", pkgver:"4.10.0-40.44")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"linux-image-4.10.0-40-lowlatency", pkgver:"4.10.0-40.44")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"linux-image-generic", pkgver:"4.10.0.40.40")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"linux-image-generic-lpae", pkgver:"4.10.0.40.40")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"linux-image-lowlatency", pkgver:"4.10.0.40.40")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"linux-image-raspi2", pkgver:"4.10.0.1021.22")) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : ubuntu_report_get()
  );
  exit(0);
}
else
{
  tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "linux-image-4.10-generic / linux-image-4.10-generic-lpae / etc");
}