RHEL 8 : kernel-rt (RHSA-2026:68532)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Red Hat Security Advisory RHSA-2026:68532. The text
# itself is copyright (C) Red Hat, Inc.
##

include('compat.inc');

if (description)
{
  script_id(346857);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/09/17");

  script_cve_id(
    "CVE-2026-23103",
    "CVE-2026-31663",
    "CVE-2026-43233",
    "CVE-2026-43339",
    "CVE-2026-46266",
    "CVE-2026-46306",
    "CVE-2026-52920",
    "CVE-2026-53075",
    "CVE-2026-53131",
    "CVE-2026-53176",
    "CVE-2026-53192",
    "CVE-2026-53223",
    "CVE-2026-53228",
    "CVE-2026-53239",
    "CVE-2026-53268",
    "CVE-2026-53275",
    "CVE-2026-63917",
    "CVE-2026-63919",
    "CVE-2026-63921",
    "CVE-2026-64002",
    "CVE-2026-68143",
    "CVE-2026-68426",
    "CVE-2026-72298"
  );
  script_xref(name:"RHSA", value:"2026:68532");

  script_name(english:"RHEL 8 : kernel-rt (RHSA-2026:68532)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Red Hat host is missing one or more security updates for kernel-rt.");
  script_set_attribute(attribute:"description", value:
"The remote Redhat Enterprise Linux 8 host has packages installed that are affected by multiple vulnerabilities as
referenced in the RHSA-2026:68532 advisory.

    The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with
    extremely high determinism requirements.

    Security Fix(es):

    * kernel: ipvlan: Make the addrs_lock be per port (CVE-2026-23103)

    * kernel: xfrm: hold dev ref until after transport_finish NF_HOOK (CVE-2026-31663)

    * kernel: netfilter: nf_conntrack_h323: fix OOB read in decode_choice() (CVE-2026-43233)

    * kernel: ipv6: prevent possible UaF in addrconf_permanent_addr() (CVE-2026-43339)

    * kernel: inet: RAW sockets using IPPROTO_RAW MUST drop incoming ICMP (CVE-2026-46266)

    * kernel: flow_dissector: do not dissect PPPoE PFC frames (CVE-2026-46306)

    * kernel: netfilter: xt_policy: fix strict mode inbound policy matching (CVE-2026-52920)

    * kernel: ppp: require CAP_NET_ADMIN in target netns for unattached ioctls (CVE-2026-53075)

    * kernel: ipv6: sit: reload inner IPv6 header after GSO offloads (CVE-2026-53228)

    * kernel: IB/isert: Reject login PDUs shorter than ISER_HEADERS_LEN (CVE-2026-53176)

    * kernel: netfilter: require Ethernet MAC header before using eth_hdr() (CVE-2026-53131)

    * kernel: netfilter: conntrack_irc: fix possible out-of-bounds read (CVE-2026-53268)

    * kernel: xfrm: policy: fix use-after-free on inexact bin in xfrm_policy_bysel_ctx() (CVE-2026-53239)

    * kernel: ALSA: timer: Fix UAF at snd_timer_user_params() (CVE-2026-53192)

    * kernel: net: guard timestamp cmsgs to real error queue skbs (CVE-2026-53223)

    * kernel: ipv6: mcast: Fix use-after-free when processing MLD queries (CVE-2026-53275)

    * kernel: ipv4: free net->ipv4.sysctl_local_reserved_ports after unregister_net_sysctl_table()
    (CVE-2026-64002)

    * kernel: ip6: vti: Use ip6_tnl.net in vti6_siocdevprivate() (CVE-2026-63921)

    * kernel: xfrm: input: hold netns during deferred transport reinjection (CVE-2026-63919)

    * kernel: ip6: vti: Use ip6_tnl.net in vti6_changelink() (CVE-2026-63917)

    * kernel: Linux kernel SLIP: Out-of-bounds write due to race condition during MTU change (CVE-2026-68143)

    * kernel: xfrm: fix stale skb->prev after async crypto steals a GSO segment (CVE-2026-68426)

    * kernel: net: qrtr: fix 32-bit integer overflow in qrtr_endpoint_post() (CVE-2026-72298)

    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/#important");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2436771");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2461462");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2467135");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2468102");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2484456");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2486463");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2492112");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2492295");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2492733");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2492741");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2492747");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2492770");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2492779");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2492792");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2492811");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2492841");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2502363");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2502368");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2502412");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2502434");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2513218");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2513477");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2516599");
  # https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_68532.json
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?6269a94b");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/errata/RHSA-2026:68532");
  script_set_attribute(attribute:"solution", value:
"Update the RHEL kernel-rt package based on the guidance in RHSA-2026:68532.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C");
  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:N/I:N/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-2026-23103");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_cwe_id(125, 131, 266, 364, 413, 551, 653, 787, 825, 826, 839, 843, 911, 1287);
  script_set_attribute(attribute:"vendor_severity", value:"Important");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/02/04");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/09/17");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/17");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:8");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:rhel_eus:8.10");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt-core");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-core");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-kvm");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-modules-extra");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt-kvm");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:kernel-rt-modules-extra");
  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: '8')) audit(AUDIT_OS_NOT, 'Red Hat 8.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-2026-23103', 'CVE-2026-31663', 'CVE-2026-43233', 'CVE-2026-43339', 'CVE-2026-46266', 'CVE-2026-46306', 'CVE-2026-52920', 'CVE-2026-53075', 'CVE-2026-53131', 'CVE-2026-53176', 'CVE-2026-53192', 'CVE-2026-53223', 'CVE-2026-53228', 'CVE-2026-53239', 'CVE-2026-53268', 'CVE-2026-53275', 'CVE-2026-63917', 'CVE-2026-63919', 'CVE-2026-63921', 'CVE-2026-64002', 'CVE-2026-68143', 'CVE-2026-68426', 'CVE-2026-72298');
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, livepatch_source + ' hotfix for RHSA-2026:68532');
  }
  else
  {
    __rpm_report = ksplice_reporting_text();
  }
}

var constraints = [
  {
    'release': '8',
    'repo_relative_urls': [
      'content/dist/rhel8/8.10/x86_64/nfv/debug',
      'content/dist/rhel8/8.10/x86_64/nfv/os',
      'content/dist/rhel8/8.10/x86_64/nfv/source/SRPMS',
      'content/dist/rhel8/8.10/x86_64/rt/debug',
      'content/dist/rhel8/8.10/x86_64/rt/os',
      'content/dist/rhel8/8.10/x86_64/rt/source/SRPMS',
      'content/dist/rhel8/8.6/x86_64/nfv/debug',
      'content/dist/rhel8/8.6/x86_64/nfv/os',
      'content/dist/rhel8/8.6/x86_64/nfv/source/SRPMS',
      'content/dist/rhel8/8.6/x86_64/rt/debug',
      'content/dist/rhel8/8.6/x86_64/rt/os',
      'content/dist/rhel8/8.6/x86_64/rt/source/SRPMS',
      'content/dist/rhel8/8.8/x86_64/nfv/debug',
      'content/dist/rhel8/8.8/x86_64/nfv/os',
      'content/dist/rhel8/8.8/x86_64/nfv/source/SRPMS',
      'content/dist/rhel8/8.8/x86_64/rt/debug',
      'content/dist/rhel8/8.8/x86_64/rt/os',
      'content/dist/rhel8/8.8/x86_64/rt/source/SRPMS',
      'content/dist/rhel8/8.9/x86_64/nfv/debug',
      'content/dist/rhel8/8.9/x86_64/nfv/os',
      'content/dist/rhel8/8.9/x86_64/nfv/source/SRPMS',
      'content/dist/rhel8/8.9/x86_64/rt/debug',
      'content/dist/rhel8/8.9/x86_64/rt/os',
      'content/dist/rhel8/8.9/x86_64/rt/source/SRPMS',
      'content/dist/rhel8/8/x86_64/nfv/debug',
      'content/dist/rhel8/8/x86_64/nfv/os',
      'content/dist/rhel8/8/x86_64/nfv/source/SRPMS',
      'content/dist/rhel8/8/x86_64/rt/debug',
      'content/dist/rhel8/8/x86_64/rt/os',
      'content/dist/rhel8/8/x86_64/rt/source/SRPMS',
      'content/e6s/rhel8/8.10/x86_64/nfv/debug',
      'content/e6s/rhel8/8.10/x86_64/nfv/os',
      'content/e6s/rhel8/8.10/x86_64/nfv/source/SRPMS',
      'content/e6s/rhel8/8.10/x86_64/rt/debug',
      'content/e6s/rhel8/8.10/x86_64/rt/os',
      'content/e6s/rhel8/8.10/x86_64/rt/source/SRPMS'
    ],
    'pkgs': [
      {'reference':'kernel-rt-4.18.0-553.164.1.rt7.505.el8_10', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-rt-core-4.18.0-553.164.1.rt7.505.el8_10', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-rt-debug-4.18.0-553.164.1.rt7.505.el8_10', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-rt-debug-core-4.18.0-553.164.1.rt7.505.el8_10', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-rt-debug-devel-4.18.0-553.164.1.rt7.505.el8_10', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-rt-debug-modules-4.18.0-553.164.1.rt7.505.el8_10', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-rt-debug-modules-extra-4.18.0-553.164.1.rt7.505.el8_10', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-rt-devel-4.18.0-553.164.1.rt7.505.el8_10', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-rt-modules-4.18.0-553.164.1.rt7.505.el8_10', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-rt-modules-extra-4.18.0-553.164.1.rt7.505.el8_10', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  },
  {
    'release': '8',
    'repo_relative_urls': [
      'content/dist/rhel8/8.10/x86_64/nfv/debug',
      'content/dist/rhel8/8.10/x86_64/nfv/os',
      'content/dist/rhel8/8.10/x86_64/nfv/source/SRPMS',
      'content/dist/rhel8/8.6/x86_64/nfv/debug',
      'content/dist/rhel8/8.6/x86_64/nfv/os',
      'content/dist/rhel8/8.6/x86_64/nfv/source/SRPMS',
      'content/dist/rhel8/8.8/x86_64/nfv/debug',
      'content/dist/rhel8/8.8/x86_64/nfv/os',
      'content/dist/rhel8/8.8/x86_64/nfv/source/SRPMS',
      'content/dist/rhel8/8.9/x86_64/nfv/debug',
      'content/dist/rhel8/8.9/x86_64/nfv/os',
      'content/dist/rhel8/8.9/x86_64/nfv/source/SRPMS',
      'content/dist/rhel8/8/x86_64/nfv/debug',
      'content/dist/rhel8/8/x86_64/nfv/os',
      'content/dist/rhel8/8/x86_64/nfv/source/SRPMS',
      'content/e6s/rhel8/8.10/x86_64/nfv/debug',
      'content/e6s/rhel8/8.10/x86_64/nfv/os',
      'content/e6s/rhel8/8.10/x86_64/nfv/source/SRPMS'
    ],
    'pkgs': [
      {'reference':'kernel-rt-debug-kvm-4.18.0-553.164.1.rt7.505.el8_10', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-rt-kvm-4.18.0-553.164.1.rt7.505.el8_10', '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_WARNING,
      extra      : extra
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'kernel-rt / kernel-rt-core / kernel-rt-debug / kernel-rt-debug-core / etc');
}