Ubuntu 16.04 ESM : Linux kernel (AWS) vulnerabilities (USN-5580-1)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-5580-1. The text
# itself is copyright (C) Canonical, Inc. See
# <https://ubuntu.com/security/notices>. Ubuntu(R) is a registered
# trademark of Canonical, Inc.
##

include('compat.inc');

if (description)
{
  script_id(164386);
  script_version("1.8");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/08/27");

  script_cve_id(
    "CVE-2021-33655",
    "CVE-2021-33656",
    "CVE-2022-20368",
    "CVE-2022-36946"
  );
  script_xref(name:"USN", value:"5580-1");

  script_name(english:"Ubuntu 16.04 ESM : Linux kernel (AWS) vulnerabilities (USN-5580-1)");

  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 16.04 ESM host has a package installed that is affected by multiple vulnerabilities as referenced in
the USN-5580-1 advisory.

    It was discovered that the framebuffer driver on the Linux kernel did not verify size limits when changing
    font or screen size, leading to an out-of- bounds write. A local attacker could use this to cause a denial
    of service (system crash) or possibly execute arbitrary code. (CVE-2021-33655)

    It was discovered that the virtual terminal driver in the Linux kernel did not properly handle VGA console
    font changes, leading to an out-of-bounds write. A local attacker could use this to cause a denial of
    service (system crash) or possibly execute arbitrary code. (CVE-2021-33656)

    It was discovered that the Packet network protocol implementation in the Linux kernel contained an out-of-
    bounds access. A remote attacker could use this to expose sensitive information (kernel memory).
    (CVE-2022-20368)

    Domingo Dirutigliano and Nicola Guerrera discovered that the netfilter subsystem in the Linux kernel did
    not properly handle rules that truncated packets below the packet header size. When such rules are in
    place, a remote attacker could possibly use this to cause a denial of service (system crash).
    (CVE-2022-36946)

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-5580-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/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:L/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-33656");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2022-20368");

  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:"2022/07/18");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/08/24");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/08/24");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:esm");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-1150-aws");
  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) 2022-2024 Canonical, Inc. / NASL script (C) 2022-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

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

  exit(0);
}

include('debian_package.inc');
include('ksplice.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 (! ('16.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 16.04', '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 ubuntu_pro_detected = get_kb_item('Host/Ubuntu/Pro/Services/esm-apps');
ubuntu_pro_detected = !empty_or_null(ubuntu_pro_detected);

var kernel_mappings = {
  '16.04': {
    '4.4.0': {
      'aws': '4.4.0-1150'
    }
  }
};

var host_kernel_release = get_kb_item('Host/uptrack-uname-r');
if (empty_or_null(host_kernel_release)) host_kernel_release = get_kb_item_or_exit('Host/uname-r');
var host_kernel_base_version = get_kb_item_or_exit('Host/Debian/kernel-base-version');
var host_kernel_type = get_kb_item_or_exit('Host/Debian/kernel-type');
if(empty_or_null(kernel_mappings[os_release][host_kernel_base_version][host_kernel_type])) audit(AUDIT_INST_VER_NOT_VULN, 'kernel ' + host_kernel_release);

var extra = '';
var kernel_fixed_version = kernel_mappings[os_release][host_kernel_base_version][host_kernel_type] + "-" + host_kernel_type;
if (!ubuntu_pro_detected) {
  extra += 'NOTE: This vulnerability check contains fixes that apply to packages only \n';
  extra += 'available in Ubuntu ESM repositories. Access to these package security updates \n';
  extra += 'require an Ubuntu Pro subscription.\n\n';
}
if (deb_ver_cmp(ver1:host_kernel_release, ver2:kernel_fixed_version) < 0)
{
  extra += 'Running Kernel level of ' + host_kernel_release + ' does not meet the minimum fixed level of ' + kernel_fixed_version + ' for this advisory.\n\n';
}
  else
{
  audit(AUDIT_PATCH_INSTALLED, 'Kernel package for USN-5580-1');
}

if (get_one_kb_item('Host/ksplice/kernel-cves'))
{
  var cve_list = make_list('CVE-2021-33655', 'CVE-2021-33656', 'CVE-2022-20368', 'CVE-2022-36946');
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, 'KSplice hotfix for USN-5580-1');
  }
  else
  {
    extra = extra + ksplice_reporting_text();
  }
}
if (extra) {
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : extra
  );
  exit(0);
}