Amazon Linux 2 : microcode_ctl, --advisory ALAS2-2025-2994 (ALAS-2025-2994)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALAS-2025-2994.
##

include('compat.inc');

if (description)
{
  script_id(265069);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/09/16");

  script_cve_id(
    "CVE-2024-28956",
    "CVE-2024-45332",
    "CVE-2025-20054",
    "CVE-2025-20103",
    "CVE-2025-20109"
  );

  script_name(english:"Amazon Linux 2 : microcode_ctl, --advisory ALAS2-2025-2994 (ALAS-2025-2994)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux 2 host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The version of microcode_ctl installed on the remote host is prior to 2.1-47. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2-2025-2994 advisory.

    A potential security vulnerability in some Intel(r) Processors may allow information disclosure. Intel is
    releasing microcode updates and prescriptive guidance to mitigate this potential vulnerability.

    Info: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-01153.html
    (CVE-2024-28956)

    Potential security vulnerabilities in some Intel(r) Processor indirect branch predictors may allow
    information disclosure. Intel is releasing microcode updates to mitigate these potential vulnerabilities.

    Advisory: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-01247.html
    (CVE-2024-45332)

    Potential security vulnerabilities in some Intel(r) Processors may allow denial of service. Intel is
    releasing microcode updates to mitigate these potential vulnerabilities.

    Advisory: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-01244.html
    (CVE-2025-20054)

    Potential security vulnerabilities in some Intel(r) Processors may allow denial of service. Intel is
    releasing microcode updates to mitigate these potential vulnerabilities.

    Advisory: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-01244.html
    (CVE-2025-20103)

    Improper Isolation or Compartmentalization in the stream cache mechanism for some Intel(R) Processors may
    allow an authenticated user to potentially enable escalation of privilege via local access.
    (CVE-2025-20109)

Tenable has extracted the preceding description block directly from the tested product 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://alas.aws.amazon.com//AL2/ALAS2-2025-2994.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/faqs.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2024-28956.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2024-45332.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2025-20054.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2025-20103.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2025-20109.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update microcode_ctl' or
  or 'yum update --advisory ALAS2-2025-2994' to update your system.");
  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:H/PR:L/UI:N/S:C/C:H/I:N/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:L/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/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-2024-45332");

  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:"2025/05/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/09/16");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/09/16");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:microcode_ctl");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:microcode_ctl-debuginfo");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Amazon Linux 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/AmazonLinux/release", "Host/AmazonLinux/rpm-list");

  exit(0);
}

include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);

var alas_release = get_kb_item("Host/AmazonLinux/release");
if (isnull(alas_release) || !strlen(alas_release)) audit(AUDIT_OS_NOT, "Amazon Linux");
var os_ver = pregmatch(pattern: "^AL(A|\d+|-\d+)", string:alas_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Amazon Linux");
os_ver = os_ver[1];
if (os_ver != "2")
{
  if (os_ver == 'A') os_ver = 'AMI';
  audit(AUDIT_OS_NOT, "Amazon Linux 2", "Amazon Linux " + os_ver);
}

if (!get_kb_item("Host/AmazonLinux/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

var pkgs = [
    {'reference':'microcode_ctl-2.1-47.amzn2.4.24', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'microcode_ctl-2.1-47.amzn2.4.24', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'microcode_ctl-debuginfo-2.1-47.amzn2.4.24', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'microcode_ctl-debuginfo-2.1-47.amzn2.4.24', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var reference = NULL;
  var _release = NULL;
  var sp = NULL;
  var _cpu = NULL;
  var el_string = NULL;
  var rpm_spec_vers_cmp = NULL;
  var epoch = NULL;
  var allowmaj = NULL;
  var exists_check = NULL;
  var cves = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) _release = package_array['release'];
  if (!empty_or_null(package_array['sp'])) sp = package_array['sp'];
  if (!empty_or_null(package_array['cpu'])) _cpu = package_array['cpu'];
  if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
  if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
  if (!empty_or_null(package_array['epoch'])) epoch = package_array['epoch'];
  if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
  if (!empty_or_null(package_array['exists_check'])) exists_check = package_array['exists_check'];
  if (!empty_or_null(package_array['cves'])) cves = package_array['cves'];
  if (reference && _release && (!exists_check || rpm_exists(release:_release, rpm:exists_check))) {
    if (rpm_check(release:_release, sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj, cves:cves)) flag++;
  }
}

if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "microcode_ctl / microcode_ctl-debuginfo");
}