Amazon Linux 2 : kernel (ALAS-2025-2834)

#%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-2025-2834.
##

include('compat.inc');

if (description)
{
  script_id(235071);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/02/24");

  script_cve_id(
    "CVE-2023-3567",
    "CVE-2023-52843",
    "CVE-2023-52845",
    "CVE-2023-52867",
    "CVE-2023-52868",
    "CVE-2023-52973"
  );

  script_name(english:"Amazon Linux 2 : kernel (ALAS-2025-2834)");

  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 kernel installed on the remote host is prior to 4.14.330-250.540. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2-2025-2834 advisory.

    A use-after-free flaw was found in vcs_read in drivers/tty/vt/vc_screen.c in vc_screen in the Linux
    Kernel. In this flaw an attacker with local user access may lead to a system crash or a leak of internal
    kernel information. (CVE-2023-3567)

    In the Linux kernel, the following vulnerability has been resolved:

    llc: verify mac len before reading mac header (CVE-2023-52843)

    In the Linux kernel, the following vulnerability has been resolved:

    tipc: Change nla_policy for bearer-related names to NLA_NUL_STRING (CVE-2023-52845)

    In the Linux kernel, the following vulnerability has been resolved:

    drm/radeon: possible buffer overflow (CVE-2023-52867)

    In the Linux kernel, the following vulnerability has been resolved:

    thermal: core: prevent potential string overflow (CVE-2023-52868)

    In the Linux kernel, the following vulnerability has been resolved:

    vc_screen: move load of struct vc_data pointer in vcs_read() to avoid UAF (CVE-2023-52973)

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/ALAS-2025-2834.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2023-3567.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2023-52843.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2023-52845.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2023-52867.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2023-52868.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2023-52973.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/faqs.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update kernel' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/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: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-2023-3567");

  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:"2021/07/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/04/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/05/01");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-debuginfo-common-aarch64");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-headers");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-livepatch-4.14.330-250.540");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-tools-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-tools-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:perf");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:perf-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python-perf");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python-perf-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) 2025-2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl", "kpatch.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/AmazonLinux/release", "Host/AmazonLinux/rpm-list");

  exit(0);
}

include("rpm.inc");
include("hotfixes.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);

if (get_one_kb_item("Host/kpatch/kernel-cves"))
{
  var cve_list = make_list("CVE-2023-3567", "CVE-2023-52843", "CVE-2023-52845", "CVE-2023-52867", "CVE-2023-52868", "CVE-2023-52973");
  if (hotfix_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "kpatch hotfix for ALAS-2025-2834");
  }
  else
  {
    __rpm_report = hotfix_reporting_text();
  }
}

var pkgs = [
    {'reference':'kernel-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-4.14.'},
    {'reference':'kernel-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-4.14.'},
    {'reference':'kernel-debuginfo-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-debuginfo-4.14.'},
    {'reference':'kernel-debuginfo-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-debuginfo-4.14.'},
    {'reference':'kernel-debuginfo-common-aarch64-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-debuginfo-common-aarch64-4.14.'},
    {'reference':'kernel-debuginfo-common-x86_64-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-debuginfo-common-x86_64-4.14.'},
    {'reference':'kernel-devel-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-devel-4.14.'},
    {'reference':'kernel-devel-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-devel-4.14.'},
    {'reference':'kernel-headers-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-headers-4.14.'},
    {'reference':'kernel-headers-4.14.330-250.540.amzn2', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-headers-4.14.'},
    {'reference':'kernel-headers-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-headers-4.14.'},
    {'reference':'kernel-livepatch-4.14.330-250.540-1.0-0.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-livepatch-4.14.330-250.540-1.0-0.'},
    {'reference':'kernel-tools-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-4.14.'},
    {'reference':'kernel-tools-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-4.14.'},
    {'reference':'kernel-tools-debuginfo-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-debuginfo-4.14.'},
    {'reference':'kernel-tools-debuginfo-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-debuginfo-4.14.'},
    {'reference':'kernel-tools-devel-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-devel-4.14.'},
    {'reference':'kernel-tools-devel-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-devel-4.14.'},
    {'reference':'perf-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'perf-4.14.'},
    {'reference':'perf-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'perf-4.14.'},
    {'reference':'perf-debuginfo-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'perf-debuginfo-4.14.'},
    {'reference':'perf-debuginfo-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'perf-debuginfo-4.14.'},
    {'reference':'python-perf-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'python-perf-4.14.'},
    {'reference':'python-perf-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'python-perf-4.14.'},
    {'reference':'python-perf-debuginfo-4.14.330-250.540.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'python-perf-debuginfo-4.14.'},
    {'reference':'python-perf-debuginfo-4.14.330-250.540.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'python-perf-debuginfo-4.14.'}
];

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, "kernel / kernel-debuginfo / kernel-debuginfo-common-x86_64 / etc");
}