Oracle Linux 8 : kernel (ELSA-2021-3057)

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Oracle Linux Security Advisory ELSA-2021-3057.
##

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

if (description)
{
  script_id(152493);
  script_version("1.11");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/01/17");

  script_cve_id("CVE-2021-3609", "CVE-2021-22543", "CVE-2021-22555");

  script_name(english:"Oracle Linux 8 : kernel (ELSA-2021-3057)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Oracle Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Oracle Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the
ELSA-2021-3057 advisory.

  - A heap out-of-bounds write affecting Linux since v2.6.19-rc1 was discovered in net/netfilter/x_tables.c.
    This allows an attacker to gain privileges or cause a DoS (via heap memory corruption) through user name
    space (CVE-2021-22555)

  - kernel: race condition in net/can/bcm.c leads to local privilege escalation (CVE-2021-3609)

  - An issue was discovered in Linux: KVM through Improper handling of VM_IO|VM_PFNMAP vmas in KVM can bypass
    RO checks and can lead to pages being freed while still accessible by the VMM and guest. This allows users
    with the ability to start and control a VM to read/write random pages of memory and can result in local
    privilege escalation. (CVE-2021-22543)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://linux.oracle.com/errata/ELSA-2021-3057.html");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  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:H/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:H/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-3609");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2021-22555");

  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:'Netfilter x_tables Heap OOB Write Privilege Escalation');
  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:"2021/04/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/08/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/08/11");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:bpftool");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-abi-stablelists");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-core");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-cross-headers");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-debug");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-debug-core");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-debug-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-debug-modules");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-debug-modules-extra");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-headers");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-modules");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-modules-extra");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-tools-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-tools-libs-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:perf");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:python3-perf");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:oracle:linux:8");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2021-2023 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("linux_alt_patch_detect.nasl", "ssh_get_info.nasl");
  script_require_keys("Host/OracleLinux", "Host/RedHat/release", "Host/RedHat/rpm-list", "Host/local_checks_enabled");

  exit(0);
}


include('audit.inc');
include('global_settings.inc');
include('ksplice.inc');
include('rpm.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item('Host/OracleLinux')) audit(AUDIT_OS_NOT, 'Oracle Linux');
var release = get_kb_item("Host/RedHat/release");
if (isnull(release) || !pregmatch(pattern: "Oracle (?:Linux Server|Enterprise Linux)", string:release)) audit(AUDIT_OS_NOT, 'Oracle Linux');
var os_ver = pregmatch(pattern: "Oracle (?:Linux Server|Enterprise Linux) .*release ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'Oracle Linux');
var os_ver = os_ver[1];
if (! preg(pattern:"^8([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, 'Oracle Linux 8', 'Oracle Linux ' + os_ver);

if (!get_kb_item('Host/RedHat/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Oracle Linux', cpu);

var machine_uptrack_level = get_one_kb_item('Host/uptrack-uname-r');
if (machine_uptrack_level)
{
  var trimmed_uptrack_level = ereg_replace(string:machine_uptrack_level, pattern:"\.(x86_64|i[3-6]86|aarch64)$", replace:'');
  var fixed_uptrack_levels = ['4.18.0-305.12.1.el8_4'];
  foreach var fixed_uptrack_level ( fixed_uptrack_levels ) {
    if (rpm_spec_vers_cmp(a:trimmed_uptrack_level, b:fixed_uptrack_level) >= 0)
    {
      audit(AUDIT_PATCH_INSTALLED, 'KSplice hotfix for ELSA-2021-3057');
    }
  }
  __rpm_report = 'Running KSplice level of ' + trimmed_uptrack_level + ' does not meet the minimum fixed level of ' + join(fixed_uptrack_levels, sep:' / ') + ' for this advisory.\n\n';
}

var kernel_major_minor = get_kb_item('Host/uname/major_minor');
if (empty_or_null(kernel_major_minor)) exit(1, 'Unable to determine kernel major-minor level.');
var expected_kernel_major_minor = '4.18';
if (kernel_major_minor != expected_kernel_major_minor)
  audit(AUDIT_OS_NOT, 'running kernel level ' + expected_kernel_major_minor + ', it is running kernel level ' + kernel_major_minor);

var pkgs = [
    {'reference':'bpftool-4.18.0-305.12.1.el8_4', 'cpu':'aarch64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bpftool-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-4.18.0'},
    {'reference':'kernel-abi-stablelists-4.18.0-305.12.1.el8_4', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-abi-stablelists-4.18.0'},
    {'reference':'kernel-core-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-core-4.18.0'},
    {'reference':'kernel-cross-headers-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-cross-headers-4.18.0'},
    {'reference':'kernel-debug-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-debug-4.18.0'},
    {'reference':'kernel-debug-core-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-debug-core-4.18.0'},
    {'reference':'kernel-debug-devel-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-debug-devel-4.18.0'},
    {'reference':'kernel-debug-modules-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-debug-modules-4.18.0'},
    {'reference':'kernel-debug-modules-extra-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-debug-modules-extra-4.18.0'},
    {'reference':'kernel-devel-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-devel-4.18.0'},
    {'reference':'kernel-headers-4.18.0-305.12.1.el8_4', 'cpu':'aarch64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-headers-4.18.0'},
    {'reference':'kernel-headers-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-headers-4.18.0'},
    {'reference':'kernel-modules-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-modules-4.18.0'},
    {'reference':'kernel-modules-extra-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-modules-extra-4.18.0'},
    {'reference':'kernel-tools-4.18.0-305.12.1.el8_4', 'cpu':'aarch64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-4.18.0'},
    {'reference':'kernel-tools-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-4.18.0'},
    {'reference':'kernel-tools-libs-4.18.0-305.12.1.el8_4', 'cpu':'aarch64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-libs-4.18.0'},
    {'reference':'kernel-tools-libs-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-libs-4.18.0'},
    {'reference':'kernel-tools-libs-devel-4.18.0-305.12.1.el8_4', 'cpu':'aarch64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-libs-devel-4.18.0'},
    {'reference':'kernel-tools-libs-devel-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-tools-libs-devel-4.18.0'},
    {'reference':'perf-4.18.0-305.12.1.el8_4', 'cpu':'aarch64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'perf-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-perf-4.18.0-305.12.1.el8_4', 'cpu':'aarch64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-perf-4.18.0-305.12.1.el8_4', 'cpu':'x86_64', 'release':'8', '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 = 'EL' + 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) {
    if (exists_check) {
        if (rpm_exists(release:release, rpm:exists_check) && 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++;
    } else {
        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 / kernel / kernel-abi-stablelists / etc');
}