RHEL 7 : kernel (RHSA-2026:27729)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Red Hat Security Advisory RHSA-2026:27729. The text
# itself is copyright (C) Red Hat, Inc.
##

include('compat.inc');

if (description)
{
  script_id(321954);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/06/22");

  script_cve_id(
    "CVE-2026-23243",
    "CVE-2026-43037",
    "CVE-2026-43110",
    "CVE-2026-43158",
    "CVE-2026-43190",
    "CVE-2026-46243"
  );
  script_xref(name:"RHSA", value:"2026:27729");

  script_name(english:"RHEL 7 : kernel (RHSA-2026:27729)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Red Hat host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Redhat Enterprise Linux 7 host has packages installed that are affected by multiple vulnerabilities as
referenced in the RHSA-2026:27729 advisory.

    The kernel packages contain the Linux kernel, the core of any Linux operating system.

    Security Fix(es):

    * kernel: Linux kernel: Denial of service and memory corruption in RDMA umad (CVE-2026-23243)

    * kernel: ip6_tunnel: clear skb2->cb[] in ip4ip6_err() (CVE-2026-43037)

    * kernel: wifi: brcmfmac: validate bsscfg indices in IF events (CVE-2026-43110)

    * kernel: netfilter: xt_tcpmss: check remaining length before reading optlen (CVE-2026-43190)

    * kernel: xfs: fix freemap adjustments when adding xattrs to leaf blocks (CVE-2026-43158)

    * kernel: Linux kernel: smb: client: reject userspace cifs.spnego descriptions (CVE-2026-46243)

    Bug Fix(es) and Enhancement(s):

    * RHEL-124698 missed the last line of the backport (JIRA:RHEL-168608)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and
    other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

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://access.redhat.com/security/updates/classification/#critical");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2448594");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2464351");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2467014");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2467064");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2467210");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2481486");
  # https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_27729.json
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?4909bb79");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/errata/RHSA-2026:27729");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/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:N/AC:L/PR:N/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-2026-43037");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_cwe_id(125, 131, 617, 825, 843, 1285);
  script_set_attribute(attribute:"vendor_severity", value:"Critical");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/03/12");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/06/22");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/06/22");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:rhel_els:7");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:bpftool");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-bootwrapper");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-debug");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-debug-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-kdump");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-kdump-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:perf");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:python-perf");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Red Hat Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

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

  exit(0);
}


include('rpm2.inc');
include('rhel.inc');
include('ksplice.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_product = get_kb_item('installed_os/local/SSH/0/product');
if (isnull(os_product) || 'Red Hat' >!< os_product) audit(AUDIT_OS_NOT, 'Red Hat');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'Red Hat');
if (!rhel_check_release(operator: 'ge', os_version: os_version, rhel_version: '7')) audit(AUDIT_OS_NOT, 'Red Hat 7.x', 'Red Hat ' + os_version);

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$" && 's390' >!< cpu && 'aarch64' >!< cpu && 'ppc' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Red Hat', cpu);

if (get_one_kb_item('Host/ksplice/kernel-cves'))
{
  var livepatch_source = get_one_kb_item('Host/livepatch-kernel-source');
  if (empty_or_null(livepatch_source)) livepatch_source = 'KSplice';
  rm_kb_item(name:'Host/livepatch-kernel-version');

  var cve_list = make_list('CVE-2026-23243', 'CVE-2026-43037', 'CVE-2026-43110', 'CVE-2026-43158', 'CVE-2026-43190', 'CVE-2026-46243');
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, livepatch_source + ' hotfix for RHSA-2026:27729');
  }
  else
  {
    __rpm_report = ksplice_reporting_text();
  }
}

var constraints = [
  {
    'release': '7',
    'repo_relative_urls': [
      'content/els/rhel/power-le/7/7Server/ppc64le/debug',
      'content/els/rhel/power-le/7/7Server/ppc64le/optional/debug',
      'content/els/rhel/power-le/7/7Server/ppc64le/optional/os',
      'content/els/rhel/power-le/7/7Server/ppc64le/optional/source/SRPMS',
      'content/els/rhel/power-le/7/7Server/ppc64le/os',
      'content/els/rhel/power-le/7/7Server/ppc64le/source/SRPMS',
      'content/els/rhel/power/7/7Server/ppc64/debug',
      'content/els/rhel/power/7/7Server/ppc64/optional/debug',
      'content/els/rhel/power/7/7Server/ppc64/optional/os',
      'content/els/rhel/power/7/7Server/ppc64/optional/source/SRPMS',
      'content/els/rhel/power/7/7Server/ppc64/os',
      'content/els/rhel/power/7/7Server/ppc64/source/SRPMS',
      'content/els/rhel/server/7/7Server/x86_64/debug',
      'content/els/rhel/server/7/7Server/x86_64/optional/debug',
      'content/els/rhel/server/7/7Server/x86_64/optional/os',
      'content/els/rhel/server/7/7Server/x86_64/optional/source/SRPMS',
      'content/els/rhel/server/7/7Server/x86_64/os',
      'content/els/rhel/server/7/7Server/x86_64/source/SRPMS',
      'content/els/rhel/system-z/7/7Server/s390x/debug',
      'content/els/rhel/system-z/7/7Server/s390x/optional/debug',
      'content/els/rhel/system-z/7/7Server/s390x/optional/os',
      'content/els/rhel/system-z/7/7Server/s390x/optional/source/SRPMS',
      'content/els/rhel/system-z/7/7Server/s390x/os',
      'content/els/rhel/system-z/7/7Server/s390x/source/SRPMS'
    ],
    'pkgs': [
      {'reference':'bpftool-3.10.0-1160.153.1.el7', 'cpu':'ppc64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'bpftool-3.10.0-1160.153.1.el7', 'cpu':'ppc64le', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'bpftool-3.10.0-1160.153.1.el7', 'cpu':'s390x', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'bpftool-3.10.0-1160.153.1.el7', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-3.10.0-1160.153.1.el7', 'cpu':'ppc64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-3.10.0-1160.153.1.el7', 'cpu':'ppc64le', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-3.10.0-1160.153.1.el7', 'cpu':'s390x', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-3.10.0-1160.153.1.el7', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-bootwrapper-3.10.0-1160.153.1.el7', 'cpu':'ppc64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-bootwrapper-3.10.0-1160.153.1.el7', 'cpu':'ppc64le', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-3.10.0-1160.153.1.el7', 'cpu':'ppc64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-3.10.0-1160.153.1.el7', 'cpu':'ppc64le', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-3.10.0-1160.153.1.el7', 'cpu':'s390x', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-3.10.0-1160.153.1.el7', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-devel-3.10.0-1160.153.1.el7', 'cpu':'ppc64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-devel-3.10.0-1160.153.1.el7', 'cpu':'ppc64le', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-devel-3.10.0-1160.153.1.el7', 'cpu':'s390x', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-devel-3.10.0-1160.153.1.el7', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-devel-3.10.0-1160.153.1.el7', 'cpu':'ppc64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-devel-3.10.0-1160.153.1.el7', 'cpu':'ppc64le', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-devel-3.10.0-1160.153.1.el7', 'cpu':'s390x', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-devel-3.10.0-1160.153.1.el7', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-kdump-3.10.0-1160.153.1.el7', 'cpu':'s390x', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-kdump-devel-3.10.0-1160.153.1.el7', 'cpu':'s390x', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-3.10.0-1160.153.1.el7', 'cpu':'ppc64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-3.10.0-1160.153.1.el7', 'cpu':'ppc64le', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-3.10.0-1160.153.1.el7', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-libs-3.10.0-1160.153.1.el7', 'cpu':'ppc64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-libs-3.10.0-1160.153.1.el7', 'cpu':'ppc64le', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-libs-3.10.0-1160.153.1.el7', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-libs-devel-3.10.0-1160.153.1.el7', 'cpu':'ppc64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-libs-devel-3.10.0-1160.153.1.el7', 'cpu':'ppc64le', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-libs-devel-3.10.0-1160.153.1.el7', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'perf-3.10.0-1160.153.1.el7', 'cpu':'ppc64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'perf-3.10.0-1160.153.1.el7', 'cpu':'ppc64le', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'perf-3.10.0-1160.153.1.el7', 'cpu':'s390x', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'perf-3.10.0-1160.153.1.el7', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python-perf-3.10.0-1160.153.1.el7', 'cpu':'ppc64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python-perf-3.10.0-1160.153.1.el7', 'cpu':'ppc64le', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python-perf-3.10.0-1160.153.1.el7', 'cpu':'s390x', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python-perf-3.10.0-1160.153.1.el7', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  }
];

var applicable_repo_urls = rhel_determine_applicable_repository_urls(constraints:constraints);
if(applicable_repo_urls == RHEL_REPOS_NO_OVERLAP_MESSAGE) exit(0, RHEL_REPO_NOT_ENABLED);

var os_release = get_one_kb_item('installed_os/local/SSH/0/release');
var os_sp = get_one_kb_item('Host/*/minor_release');

var flag = 0;
var repo_relative_urls;
var reference;
var sp;
var _cpu;
var el_string;
var rpm_spec_vers_cmp;
var epoch;
var allowmaj;
var exists_check;
var cves;
foreach var constraint ( constraints ) {
  # Check that the target release is equal to the affected release
  if (!empty_or_null(constraint['release'])){
    if (constraint['release'] != os_release) continue;
  }
  if (!empty_or_null(constraint['sp'])){
    if (constraint['sp'] != os_sp) continue;
  }

  if (!empty_or_null(constraint['repo_relative_urls'])) repo_relative_urls = constraint['repo_relative_urls'];

  foreach var pkg ( constraint['pkgs'] ) {
    reference = NULL;
    sp = NULL;
    _cpu = NULL;
    el_string = NULL;
    rpm_spec_vers_cmp = NULL;
    epoch = NULL;
    allowmaj = NULL;
    exists_check = NULL;
    cves = NULL;
    if (!empty_or_null(pkg['reference'])) reference = pkg['reference'];
    if (!empty_or_null(pkg['sp'])) sp = pkg['sp'];
    if (!empty_or_null(pkg['cpu'])) _cpu = pkg['cpu'];
    if (!empty_or_null(pkg['el_string'])) el_string = pkg['el_string'];
    if (!empty_or_null(pkg['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = pkg['rpm_spec_vers_cmp'];
    if (!empty_or_null(pkg['epoch'])) epoch = pkg['epoch'];
    if (!empty_or_null(pkg['allowmaj'])) allowmaj = pkg['allowmaj'];
    if (!empty_or_null(pkg['exists_check'])) exists_check = pkg['exists_check'];
    if (!empty_or_null(pkg['cves'])) cves = pkg['cves'];
    if (reference &&
        rhel_decide_repo_relative_url_check(required_repo_url_list:repo_relative_urls) &&
        (applicable_repo_urls || (!exists_check || rpm_exists(rpm:exists_check))) &&
        rpm_check(sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj, cves:cves)) flag++;
  }
}

if (flag)
{
  var extra = NULL;
  if (isnull(applicable_repo_urls) || !applicable_repo_urls) extra = rpm_report_get() + redhat_report_repo_caveat();
  else extra = rpm_report_get();
  security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      extra      : extra
  );
  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-bootwrapper / kernel-debug / etc');
}