Oracle Linux 6 / 7 : Unbreakable Enterprise kernel (ELSA-2019-4729)

#%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-2019-4729.
##

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

if (description)
{
  script_id(127613);
  script_version("1.5");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/09/08");

  script_cve_id(
    "CVE-2018-20169",
    "CVE-2019-11833",
    "CVE-2019-12378",
    "CVE-2019-12381"
  );

  script_name(english:"Oracle Linux 6 / 7 : Unbreakable Enterprise kernel (ELSA-2019-4729)");

  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 6 / 7 host has packages installed that are affected by multiple vulnerabilities as referenced in
the ELSA-2019-4729 advisory.

  - An issue was discovered in the Linux kernel before 4.19.9. The USB subsystem mishandles size checks during
    the reading of an extra descriptor, related to __usb_get_extra_descriptor in drivers/usb/core/usb.c.
    (CVE-2018-20169)

  - fs/ext4/extents.c in the Linux kernel through 5.1.2 does not zero out the unused memory region in the
    extent tree block, which might allow local users to obtain sensitive information by reading uninitialized
    data in the filesystem. (CVE-2019-11833)

  - ** DISPUTED ** An issue was discovered in ip6_ra_control in net/ipv6/ipv6_sockglue.c in the Linux kernel
    through 5.1.5. There is an unchecked kmalloc of new_ra, which might allow an attacker to cause a denial of
    service (NULL pointer dereference and system crash). NOTE: This has been disputed as not an issue.
    (CVE-2019-12378)

  - ** DISPUTED ** An issue was discovered in ip_ra_control in net/ipv4/ip_sockglue.c in the Linux kernel
    through 5.1.5. There is an unchecked kmalloc of new_ra, which might allow an attacker to cause a denial of
    service (NULL pointer dereference and system crash). NOTE: this is disputed because new_ra is never used
    if it is NULL. (CVE-2019-12381)

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-2019-4729.html");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/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:P/AC:L/PR:N/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-2018-20169");

  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:"2018/12/17");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/07/29");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/08/12");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:oracle:linux:6");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:oracle:linux:7");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-uek");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-uek-debug");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-uek-debug-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-uek-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-uek-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:kernel-uek-firmware");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2019-2021 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:"^(6|7)([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, 'Oracle Linux 6 / 7', '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);
if ('x86_64' >!< cpu) audit(AUDIT_ARCH_NOT, 'x86_64', 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 = ['4.1.12-124.29.3.el6uek', '4.1.12-124.29.3.el7uek'];
  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-2019-4729');
    }
  }
  __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 = '4.1';
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':'kernel-uek-4.1.12-124.29.3.el6uek', 'cpu':'x86_64', 'release':'6', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-4.1.12'},
    {'reference':'kernel-uek-debug-4.1.12-124.29.3.el6uek', 'cpu':'x86_64', 'release':'6', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-debug-4.1.12'},
    {'reference':'kernel-uek-debug-devel-4.1.12-124.29.3.el6uek', 'cpu':'x86_64', 'release':'6', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-debug-devel-4.1.12'},
    {'reference':'kernel-uek-devel-4.1.12-124.29.3.el6uek', 'cpu':'x86_64', 'release':'6', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-devel-4.1.12'},
    {'reference':'kernel-uek-doc-4.1.12-124.29.3.el6uek', 'release':'6', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-doc-4.1.12'},
    {'reference':'kernel-uek-firmware-4.1.12-124.29.3.el6uek', 'release':'6', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-firmware-4.1.12'},
    {'reference':'kernel-uek-4.1.12-124.29.3.el7uek', 'cpu':'x86_64', 'release':'7', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-4.1.12'},
    {'reference':'kernel-uek-debug-4.1.12-124.29.3.el7uek', 'cpu':'x86_64', 'release':'7', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-debug-4.1.12'},
    {'reference':'kernel-uek-debug-devel-4.1.12-124.29.3.el7uek', 'cpu':'x86_64', 'release':'7', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-debug-devel-4.1.12'},
    {'reference':'kernel-uek-devel-4.1.12-124.29.3.el7uek', 'cpu':'x86_64', 'release':'7', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-devel-4.1.12'},
    {'reference':'kernel-uek-doc-4.1.12-124.29.3.el7uek', 'release':'7', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-doc-4.1.12'},
    {'reference':'kernel-uek-firmware-4.1.12-124.29.3.el7uek', 'release':'7', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'kernel-uek-firmware-4.1.12'}
];

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_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, 'kernel-uek / kernel-uek-debug / kernel-uek-debug-devel / etc');
}