Ubuntu 14.04 LTS / Pro FIPS 16.04 LTS : Linux kernel vulnerabilities (USN-8548-1)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-8548-1. 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(327343);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/17");

  script_cve_id(
    "CVE-2021-47117",
    "CVE-2021-47202",
    "CVE-2023-52646",
    "CVE-2024-56643",
    "CVE-2026-23455",
    "CVE-2026-31402",
    "CVE-2026-31607",
    "CVE-2026-31637",
    "CVE-2026-31659",
    "CVE-2026-31685",
    "CVE-2026-43011",
    "CVE-2026-43037",
    "CVE-2026-43038",
    "CVE-2026-43383",
    "CVE-2026-43407",
    "CVE-2026-43414",
    "CVE-2026-43503",
    "CVE-2026-45988",
    "CVE-2026-46119",
    "CVE-2026-46243"
  );
  script_xref(name:"USN", value:"8548-1");

  script_name(english:"Ubuntu 14.04 LTS / Pro FIPS 16.04 LTS : Linux kernel vulnerabilities (USN-8548-1)");

  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 14.04 LTS / Pro FIPS 16.04 LTS host has a package installed that is affected by multiple
vulnerabilities as referenced in the USN-8548-1 advisory.

    It was discovered that a logic flaw existed in the XFRM ESP-in-TCP subsystem in the Linux kernel when
    handling socket buffer fragments. This flaw is known as Fragnesia. A local attacker could use this to
    escalate privileges, or possibly escape a container. (CVE-2026-43503)

    Several security issues were discovered in the Linux kernel. An attacker could possibly use these to
    compromise the system. This update corrects flaws in the following subsystems:

    - SCSI subsystem;

    - Thermal drivers;

    - USB over IP driver;

    - File systems infrastructure;

    - Ext4 file system;

    - Network file system (NFS) server daemon;

    - SMB network file system;

    - Tracing infrastructure;

    - B.A.T.M.A.N. meshing protocol;

    - Ceph Core library;

    - DCCP (Datagram Congestion Control Protocol);

    - IPv4 networking;

    - IPv6 networking;

    - Netfilter;

    - RxRPC session sockets;

    - X.25 network layer; (CVE-2021-47117, CVE-2021-47202, CVE-2023-52646, CVE-2024-56643, CVE-2026-23455,
    CVE-2026-31402, CVE-2026-31607, CVE-2026-31637, CVE-2026-31659, CVE-2026-31685, CVE-2026-43011,
    CVE-2026-43037, CVE-2026-43038, CVE-2026-43383, CVE-2026-43407, CVE-2026-43414, CVE-2026-45988,
    CVE-2026-46119, CVE-2026-46243)

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-8548-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:C");
  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_cvss3_temporal_vector("CVSS:3.0/E:F/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2024-56643");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"exploit_framework_core", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2021/07/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/07/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/16");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:Pro:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-1126-fips");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-1156-aws");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-283-generic");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-4.4.0-283-lowlatency");
  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) 2026 Canonical, Inc. / NASL script (C) 2026 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 (! ('14.04' >< os_release || 'Pro' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 14.04 / Pro', '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 = {
  '14.04': {
    '4.4.0': {
      'generic': '4.4.0-283',
      'lowlatency': '4.4.0-283',
      'aws': '4.4.0-1156'
    }
  },
  'Pro': {
    '4.4.0': {
      'fips': '4.4.0-1126'
    }
  }
};

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-8548-1');
}

if (get_one_kb_item('Host/ksplice/kernel-cves'))
{
  var cve_list = make_list('CVE-2021-47117', 'CVE-2021-47202', 'CVE-2023-52646', 'CVE-2024-56643', 'CVE-2026-23455', 'CVE-2026-31402', 'CVE-2026-31607', 'CVE-2026-31637', 'CVE-2026-31659', 'CVE-2026-31685', 'CVE-2026-43011', 'CVE-2026-43037', 'CVE-2026-43038', 'CVE-2026-43383', 'CVE-2026-43407', 'CVE-2026-43414', 'CVE-2026-43503', 'CVE-2026-45988', 'CVE-2026-46119', 'CVE-2026-46243');
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, 'KSplice hotfix for USN-8548-1');
  }
  else
  {
    extra = extra + ksplice_reporting_text();
  }
}
if (extra) {
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : extra
  );
  exit(0);
}