Ubuntu 16.04 LTS : linux, linux-aws, linux-kvm, linux-raspi2, linux-snapdragon vulnerability (USN-4320-1)

2020-04-07T00:00:00
ID UBUNTU_USN-4320-1.NASL
Type nessus
Reporter Ubuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
Modified 2020-04-07T00:00:00

Description

Al Viro discovered that the vfs layer in the Linux kernel contained a use- after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly expose sensitive information (kernel memory).

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-4320-1. 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(135271);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/04/10");

  script_cve_id("CVE-2020-8428");
  script_xref(name:"USN", value:"4320-1");

  script_name(english:"Ubuntu 16.04 LTS : linux, linux-aws, linux-kvm, linux-raspi2, linux-snapdragon vulnerability (USN-4320-1)");
  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:
"Al Viro discovered that the vfs layer in the Linux kernel contained a
use- after-free vulnerability. A local attacker could use this to
cause a denial of service (system crash) or possibly expose sensitive
information (kernel memory).

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/4320-1/"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/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:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4-aws");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4-generic");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4-generic-lpae");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4-kvm");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4-lowlatency");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4-raspi2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4-snapdragon");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-aws");
  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-generic-lpae-lts-xenial");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lts-xenial");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-kvm");
  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-lowlatency-lts-xenial");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-snapdragon");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-lts-xenial");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/01/29");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/04/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/04/07");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 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:"^(14\.04|16\.04)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 14.04 / 16.04", "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-2020-8428");
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "KSplice hotfix for USN-4320-1");
  }
  else
  {
    _ubuntu_report = ksplice_reporting_text();
  }
}

flag = 0;

if (ubuntu_check(osver:"16.04", pkgname:"linux-image-4.4.0-1069-kvm", pkgver:"4.4.0-1069.76")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-4.4.0-1105-aws", pkgver:"4.4.0-1105.116")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-4.4.0-1131-raspi2", pkgver:"4.4.0-1131.140")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-4.4.0-1135-snapdragon", pkgver:"4.4.0-1135.143")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-4.4.0-177-generic", pkgver:"4.4.0-177.207")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-4.4.0-177-generic-lpae", pkgver:"4.4.0-177.207")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-4.4.0-177-lowlatency", pkgver:"4.4.0-177.207")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-aws", pkgver:"4.4.0.1105.109")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-generic", pkgver:"4.4.0.177.185")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-generic-lpae", pkgver:"4.4.0.177.185")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-kvm", pkgver:"4.4.0.1069.69")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-lowlatency", pkgver:"4.4.0.177.185")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-raspi2", pkgver:"4.4.0.1131.131")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-snapdragon", pkgver:"4.4.0.1135.127")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"linux-image-virtual", pkgver:"4.4.0.177.185")) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_NOTE,
    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-4.4-aws / linux-image-4.4-generic / etc");
}