Amazon Linux 2 : kernel (ALASKERNEL-5.4-2022-009)

##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALASKERNEL-5.4-2022-009.
##

include('compat.inc');

if (description)
{
  script_id(160436);
  script_version("1.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/09/05");

  script_cve_id(
    "CVE-2019-18808",
    "CVE-2021-3744",
    "CVE-2021-3764",
    "CVE-2021-20322",
    "CVE-2021-41864"
  );

  script_name(english:"Amazon Linux 2 : kernel (ALASKERNEL-5.4-2022-009)");

  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 5.4.156-83.273. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2KERNEL-5.4-2022-009 advisory.

  - A flaw in the processing of received ICMP errors (ICMP fragment needed and ICMP redirect) in the Linux
    kernel functionality was found to allow the ability to quickly scan open UDP ports. This flaw allows an
    off-path remote user to effectively bypass the source port UDP randomization. The highest threat from this
    vulnerability is to confidentiality and possibly integrity, because software that relies on UDP source
    port randomization are indirectly affected as well. (CVE-2021-20322)

  - A memory leak in the ccp_run_sha_cmd() function in drivers/crypto/ccp/ccp-ops.c in the Linux kernel
    through 5.3.9 allows attackers to cause a denial of service (memory consumption), aka CID-128c66429247.
    (CVE-2019-18808)

  - A memory leak flaw was found in the Linux kernel in the ccp_run_aes_gcm_cmd() function in
    drivers/crypto/ccp/ccp-ops.c, which allows attackers to cause a denial of service (memory consumption).
    This vulnerability is similar with the older CVE-2019-18808. (CVE-2021-3744)

  - A memory leak flaw was found in the Linux kernel's ccp_run_aes_gcm_cmd() function that allows an attacker
    to cause a denial of service. The vulnerability is similar to the older CVE-2019-18808. The highest threat
    from this vulnerability is to system availability. (CVE-2021-3764)

  - prealloc_elems_and_freelist in kernel/bpf/stackmap.c in the Linux kernel before 5.14.12 allows
    unprivileged users to trigger an eBPF multiplication integer overflow with a resultant out-of-bounds
    write. (CVE-2021-41864)

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/ALASKERNEL-5.4-2022-009.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-20322.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-3744.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-3764.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-41864.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update kernel' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:POC/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:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-20322");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2021-41864");

  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:"2019/11/07");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/01/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/05/02");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bpftool");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bpftool-debuginfo");
  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-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_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2022-2023 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-2019-18808", "CVE-2021-3744", "CVE-2021-3764", "CVE-2021-20322", "CVE-2021-41864");
  if (hotfix_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "kpatch hotfix for ALASKERNEL-5.4-2022-009");
  }
  else
  {
    __rpm_report = hotfix_reporting_text();
  }
}
var pkgs = [
    {'reference':'bpftool-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'bpftool-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'bpftool-debuginfo-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'bpftool-debuginfo-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-debuginfo-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-debuginfo-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-debuginfo-common-aarch64-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-debuginfo-common-x86_64-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-devel-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-devel-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-headers-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-headers-5.4.156-83.273.amzn2', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-headers-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-tools-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-tools-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-tools-debuginfo-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-tools-debuginfo-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-tools-devel-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'kernel-tools-devel-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'perf-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'perf-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'perf-debuginfo-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'perf-debuginfo-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'python-perf-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'python-perf-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'python-perf-debuginfo-5.4.156-83.273.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'},
    {'reference':'python-perf-debuginfo-5.4.156-83.273.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.4'}
];

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, "bpftool / bpftool-debuginfo / kernel / etc");
}