Amazon Linux 2 : kernel (ALASKERNEL-5.10-2022-011)

##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALASKERNEL-5.10-2022-011.
##

include('compat.inc');

if (description)
{
  script_id(160425);
  script_version("1.12");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/09/05");

  script_cve_id(
    "CVE-2021-4197",
    "CVE-2021-26341",
    "CVE-2021-26401",
    "CVE-2022-0001",
    "CVE-2022-0002",
    "CVE-2022-0435",
    "CVE-2022-0847",
    "CVE-2022-1055",
    "CVE-2022-2964",
    "CVE-2022-23960"
  );
  script_xref(name:"CISA-KNOWN-EXPLOITED", value:"2022/05/16");

  script_name(english:"Amazon Linux 2 : kernel (ALASKERNEL-5.10-2022-011)");

  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 5.10.102-99.473. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2KERNEL-5.10-2022-011 advisory.

  - Some AMD CPUs may transiently execute beyond unconditional direct branches, which may potentially result
    in data leakage. (CVE-2021-26341)

  - LFENCE/JMP (mitigation V2-2) may not sufficiently mitigate CVE-2017-5715 on some AMD CPUs.
    (CVE-2021-26401)

  - An unprivileged write to the file handler flaw in the Linux kernel's control groups and namespaces
    subsystem was found in the way users have access to some less privileged process that are controlled by
    cgroups and have higher privileged parent process. It is actually both for cgroup2 and cgroup1 versions of
    control groups. A local user could use this flaw to crash the system or escalate their privileges on the
    system. (CVE-2021-4197)

  - Non-transparent sharing of branch predictor selectors between contexts in some Intel(R) Processors may
    allow an authorized user to potentially enable information disclosure via local access. (CVE-2022-0001)

  - Non-transparent sharing of branch predictor within a context in some Intel(R) Processors may allow an
    authorized user to potentially enable information disclosure via local access. (CVE-2022-0002)

  - A stack overflow flaw was found in the Linux kernel's TIPC protocol functionality in the way a user sends
    a packet with malicious content where the number of domain member nodes is higher than the 64 allowed.
    This flaw allows a remote user to crash the system or possibly escalate their privileges if they have
    access to the TIPC network. (CVE-2022-0435)

  - A flaw was found in the way the flags member of the new pipe buffer structure was lacking proper
    initialization in copy_page_to_iter_pipe and push_pipe functions in the Linux kernel and could thus
    contain stale values. An unprivileged local user could use this flaw to write to pages in the page cache
    backed by read only files and as such escalate their privileges on the system. (CVE-2022-0847)

  - A use-after-free exists in the Linux Kernel in tc_new_tfilter that could allow a local attacker to gain
    privilege escalation. The exploit requires unprivileged user namespaces. We recommend upgrading past
    commit 04c2a47ffb13c29778e2a14e414ad4cb5a5db4b5 (CVE-2022-1055)

  - Certain Arm Cortex and Neoverse processors through 2022-03-08 do not properly restrict cache speculation,
    aka Spectre-BHB. An attacker can leverage the shared branch history in the Branch History Buffer (BHB) to
    influence mispredicted branches. Then, cache allocation can allow the attacker to obtain sensitive
    information. (CVE-2022-23960)

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-5.10-2022-011.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-26341.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-26401.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-4197.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2022-0001.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2022-0002.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2022-0435.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2022-0847.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2022-1055.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2022-23960.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2022-2964.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update kernel' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:H/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:H/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2022-0435");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"exploit_framework_core", value:"true");
  script_set_attribute(attribute:"exploited_by_malware", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'Dirty Pipe Local Privilege Escalation via CVE-2022-0847');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");
  script_set_attribute(attribute:"exploit_framework_canvas", value:"true");
  script_set_attribute(attribute:"canvas_package", value:"CANVAS");

  script_set_attribute(attribute:"vuln_publication_date", value:"2022/03/07");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/03/07");
  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-livepatch-5.10.102-99.473");
  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-2021-4197", "CVE-2021-26341", "CVE-2021-26401", "CVE-2022-0001", "CVE-2022-0002", "CVE-2022-0435", "CVE-2022-0847", "CVE-2022-1055", "CVE-2022-2964", "CVE-2022-23960");
  if (hotfix_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "kpatch hotfix for ALASKERNEL-5.10-2022-011");
  }
  else
  {
    __rpm_report = hotfix_reporting_text();
  }
}
var pkgs = [
    {'reference':'bpftool-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'bpftool-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'bpftool-debuginfo-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'bpftool-debuginfo-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-debuginfo-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-debuginfo-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-debuginfo-common-aarch64-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-debuginfo-common-x86_64-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-devel-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-devel-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-headers-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-headers-5.10.102-99.473.amzn2', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-headers-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-livepatch-5.10.102-99.473-1.0-0.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-livepatch-5.10.102-99.473-1.0-0.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-tools-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-tools-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-tools-debuginfo-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-tools-debuginfo-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-tools-devel-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'kernel-tools-devel-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'perf-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'perf-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'perf-debuginfo-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'perf-debuginfo-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'python-perf-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'python-perf-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'python-perf-debuginfo-5.10.102-99.473.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'},
    {'reference':'python-perf-debuginfo-5.10.102-99.473.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-5.10'}
];

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_HOLE,
      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");
}