Amazon Linux 2 : kernel (ALAS-2021-1727)

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALAS-2021-1727.
##

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(155973);
  script_version("1.8");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/02/07");

  script_cve_id(
    "CVE-2021-3640",
    "CVE-2021-3772",
    "CVE-2021-4002",
    "CVE-2023-0047"
  );
  script_xref(name:"ALAS", value:"2021-1727");

  script_name(english:"Amazon Linux 2 : kernel (ALAS-2021-1727)");

  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 4.14.256-197.484. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2-2021-1727 advisory.

  - A flaw use-after-free in function sco_sock_sendmsg() of the Linux kernel HCI subsystem was found in the
    way user calls ioct UFFDIO_REGISTER or other way triggers race condition of the call sco_conn_del()
    together with the call sco_sock_sendmsg() with the expected controllable faulting memory page. A
    privileged local user could use this flaw to crash the system or escalate their privileges on the system.
    (CVE-2021-3640)

  - A flaw was found in the Linux SCTP stack. A blind attacker may be able to kill an existing SCTP
    association through invalid chunks if the attacker knows the IP-addresses and port numbers being used and
    the attacker can send packets with spoofed IP addresses. (CVE-2021-3772)

  - A memory leak flaw in the Linux kernel's hugetlbfs memory usage was found in the way the user maps some
    regions of memory twice using shmget() which are aligned to PUD alignment with the fault of some of the
    memory pages. A local user could use this flaw to get unauthorized access to some data. (CVE-2021-4002)

  - Rejected reason: DO NOT USE THIS CANDIDATE NUMBER. ConsultIDs: none. Reason: This candidate was in a CNA
    pool that was not assigned to any issues during 2023. Notes: none. (CVE-2023-0047)

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-2021-1727.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-3640.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-3772.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-4002.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2023-0047.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:M/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-3640");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2021/12/08");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/12/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/12/10");

  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-4.14.256-197.484");
  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) 2021-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("kpatch.nasl", "ssh_get_info.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"))
{
  set_hotfix_type("kpatch");
  var cve_list = make_list("CVE-2021-3640", "CVE-2021-3772", "CVE-2021-4002", "CVE-2023-0047");
  if (hotfix_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "kpatch hotfix for ALAS-2021-1727");
  }
  else
  {
    __rpm_report = hotfix_reporting_text();
  }
}
var pkgs = [
    {'reference':'kernel-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-4.14.256-197.484.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-debuginfo-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-debuginfo-4.14.256-197.484.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-debuginfo-common-aarch64-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-debuginfo-common-x86_64-4.14.256-197.484.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-devel-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-devel-4.14.256-197.484.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-headers-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-headers-4.14.256-197.484.amzn2', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-headers-4.14.256-197.484.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-livepatch-4.14.256-197.484-1.0-0.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-4.14.256-197.484.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-debuginfo-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-debuginfo-4.14.256-197.484.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-devel-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-devel-4.14.256-197.484.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'perf-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'perf-4.14.256-197.484.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'perf-debuginfo-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'perf-debuginfo-4.14.256-197.484.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python-perf-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python-perf-4.14.256-197.484.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python-perf-debuginfo-4.14.256-197.484.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python-perf-debuginfo-4.14.256-197.484.amzn2', '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;
  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 (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)) 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");
}