Debian dla-4347 : intel-microcode - security update

#%NASL_MIN_LEVEL 80900
#
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory dla-4347. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(271445);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/10/25");

  script_cve_id(
    "CVE-2025-20053",
    "CVE-2025-20109",
    "CVE-2025-21090",
    "CVE-2025-22839",
    "CVE-2025-22840",
    "CVE-2025-22889",
    "CVE-2025-24305",
    "CVE-2025-26403",
    "CVE-2025-32086"
  );

  script_name(english:"Debian dla-4347 : intel-microcode - security update");

  script_set_attribute(attribute:"synopsis", value:
"The remote Debian host is missing one or more security-related updates.");
  script_set_attribute(attribute:"description", value:
"The remote Debian 11 host has a package installed that is affected by multiple vulnerabilities as referenced in the
dla-4347 advisory.

    -------------------------------------------------------------------------
    Debian LTS Advisory DLA-4347-1                [email protected]
    https://www.debian.org/lts/security/                         Tobias Frost
    October 25, 2025                              https://wiki.debian.org/LTS
    -------------------------------------------------------------------------

    Package        : intel-microcode
    Version        : 3.20250812.1~deb11u1
    CVE ID         : CVE-2025-20053 CVE-2025-20109 CVE-2025-21090 CVE-2025-22839
                     CVE-2025-22840 CVE-2025-22889 CVE-2025-24305 CVE-2025-26403
                     CVE-2025-32086
    Debian Bug     : 1110983 1112168

    This update ships updated CPU microcode for some types of Intel CPUs and
    provides mitigations for security vulnerabilities which could result in
    privilege escalation or denial of service.

    For Debian 11 bullseye, these problems have been fixed in version
    3.20250812.1~deb11u1.

    We recommend that you upgrade your intel-microcode packages.

    For the detailed security status of intel-microcode please refer to
    its security tracker page at:
    https://security-tracker.debian.org/tracker/intel-microcode

    Further information about Debian LTS security advisories, how to apply
    these updates to your system and frequently asked questions can be
    found at: https://wiki.debian.org/LTS
    Attachment:
    signature.asc
    Description: PGP signature

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

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  # https://security-tracker.debian.org/tracker/source-package/intel-microcode
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?019586d4");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-20053");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-20109");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-21090");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-22839");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-22840");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-22889");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-24305");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-26403");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2025-32086");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bullseye/intel-microcode");
  script_set_attribute(attribute:"solution", value:
"Upgrade the intel-microcode packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:H/Au:S/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:H/UI:N/S:C/C:H/I:H/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:A/AC:H/AT:P/PR:H/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2025-20109");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2025-22889");
  script_set_attribute(attribute:"cvss4_score_source", value:"CVE-2025-22839");

  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:"2025/08/12");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/10/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/10/25");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:intel-microcode");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2025 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Debian/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);
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);

var debian_release = get_kb_item('Host/Debian/release');
if ( isnull(debian_release) ) audit(AUDIT_OS_NOT, 'Debian');
debian_release = chomp(debian_release);
if (! preg(pattern:"^(11)\.[0-9]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 11.0', 'Debian ' + debian_release);
var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Debian', cpu);

var pkgs = [
    {'release': '11.0', 'prefix': 'intel-microcode', 'reference': '3.20250812.1~deb11u1'}
];

var flag = 0;
foreach package_array ( pkgs ) {
  var _release = NULL;
  var prefix = NULL;
  var reference = NULL;
  if (!empty_or_null(package_array['release'])) _release = package_array['release'];
  if (!empty_or_null(package_array['prefix'])) prefix = package_array['prefix'];
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (_release && prefix && reference) {
    if (deb_check(release:_release, prefix:prefix, reference:reference)) flag++;
  }
}

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : deb_report_get()
  );
  exit(0);
}
else
{
  var tested = deb_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'intel-microcode');
}