Ubuntu 18.04 LTS / 20.04 LTS : Intel Microcode vulnerabilities (USN-4628-3)

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-4628-3. The text
# itself is copyright (C) Canonical, Inc. See
# <https://ubuntu.com/security/notices>. Ubuntu(R) is a registered
# trademark of Canonical, Inc.
##

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(149521);
  script_version("1.5");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/08/27");

  script_cve_id("CVE-2020-8695", "CVE-2020-8696", "CVE-2020-8698");
  script_xref(name:"USN", value:"4628-3");

  script_name(english:"Ubuntu 18.04 LTS / 20.04 LTS : Intel Microcode vulnerabilities (USN-4628-3)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Ubuntu 18.04 LTS / 20.04 LTS host has a package installed that is affected by multiple vulnerabilities as
referenced in the USN-4628-3 advisory.

    USN-4628-1 provided updated Intel Processor Microcode for various processor types.

    This update provides the corresponding updates for some additional processor types.

    Original advisory details:

    Moritz Lipp, Michael Schwarz, Andreas Kogler, David Oswald, Catherine

    Easdon, Claudio Canella, and Daniel Gruss discovered that the Intel Running

    Average Power Limit (RAPL) feature of some Intel processors allowed a side-

    channel attack based on power consumption measurements. A local attacker

    could possibly use this to expose sensitive information. (CVE-2020-8695)

    Ezra Caltum, Joseph Nuzman, Nir Shildan and Ofir Joseff discovered that

    some Intel(R) Processors did not properly remove sensitive information

    before storage or transfer in some situations. A local attacker could

    possibly use this to expose sensitive information. (CVE-2020-8696)

    Ezra Caltum, Joseph Nuzman, Nir Shildan and Ofir Joseff discovered that

    some Intel(R) Processors did not properly isolate shared resources in some

    situations. A local attacker could possibly use this to expose sensitive

    information. (CVE-2020-8698)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/notices/USN-4628-3");
  script_set_attribute(attribute:"solution", value:
"Update the affected intel-microcode package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/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:L/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-2020-8698");

  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:"2020/11/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/05/17");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/05/17");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:intel-microcode");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"Ubuntu Security Notice (C) 2021-2024 Canonical, Inc. / NASL script (C) 2021-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

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

  exit(0);
}

include('debian_package.inc');

if ( ! get_kb_item('Host/local_checks_enabled') ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/Ubuntu/release');
if ( isnull(os_release) ) audit(AUDIT_OS_NOT, 'Ubuntu');
os_release = chomp(os_release);
if (! ('18.04' >< os_release || '20.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 18.04 / 20.04', 'Ubuntu ' + os_release);
if ( ! get_kb_item('Host/Debian/dpkg-l') ) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 's390' >!< cpu && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Ubuntu', cpu);

var pkgs = [
    {'osver': '18.04', 'pkgname': 'intel-microcode', 'pkgver': '3.20210216.0ubuntu0.18.04.1'},
    {'osver': '20.04', 'pkgname': 'intel-microcode', 'pkgver': '3.20210216.0ubuntu0.20.04.1'}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var osver = NULL;
  var pkgname = NULL;
  var pkgver = NULL;
  if (!empty_or_null(package_array['osver'])) osver = package_array['osver'];
  if (!empty_or_null(package_array['pkgname'])) pkgname = package_array['pkgname'];
  if (!empty_or_null(package_array['pkgver'])) pkgver = package_array['pkgver'];
  if (osver && pkgname && pkgver) {
    if (ubuntu_check(osver:osver, pkgname:pkgname, pkgver:pkgver)) flag++;
  }
}

if (flag)
{
  var extra = '';
  extra += ubuntu_report_get();
  security_report_v4(
    port       : 0,
    severity   : SECURITY_NOTE,
    extra      : extra
  );
  exit(0);
}
else
{
  var tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'intel-microcode');
}