CentOS Linux 8 [TuxCare] Security Update: bpftool / kernel / kernel-core / kernel-cross-headers / etc Multiple Vulnerabilities (CENTOS-STREAM8:CLSA-2026:1782375682)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(361917);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/01");

  script_cve_id(
    "CVE-2022-49975",
    "CVE-2022-50051",
    "CVE-2023-52504",
    "CVE-2023-52818",
    "CVE-2025-38361",
    "CVE-2025-68366",
    "CVE-2025-71082",
    "CVE-2025-71091",
    "CVE-2026-23099",
    "CVE-2026-23191",
    "CVE-2026-23243",
    "CVE-2026-23270",
    "CVE-2026-23455",
    "CVE-2026-31405",
    "CVE-2026-31532",
    "CVE-2026-31581",
    "CVE-2026-31685",
    "CVE-2026-43027",
    "CVE-2026-43110",
    "CVE-2026-43158",
    "CVE-2026-43190",
    "CVE-2026-43370"
  );
  script_xref(name:"CLSA", value:"2026:1782375682");

  script_name(english:"CentOS Linux 8 [TuxCare] Security Update: bpftool / kernel / kernel-core / kernel-cross-headers / etc Multiple Vulnerabilities (CENTOS-STREAM8:CLSA-2026:1782375682)");

  script_set_attribute(attribute:"synopsis", value:
"The CentOS Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The CentOS Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the
TuxCare CENTOS-STREAM8:CLSA-2026:1782375682 advisory.

  - In the Linux kernel, the following vulnerability has been resolved: bpf: Don't redirect packets with
    invalid pkt_len Syzbot found an issue [1]: fq_codel_drop() try to drop a flow whitout any skbs, that is,
    the flow->head is null. The root cause, as the [2] says, is because that bpf_prog_test_run_skb() run a bpf
    prog which redirects empty skbs. So we should determine whether the length of the packet modified by bpf
    prog or others like bpf_prog_test is valid before forwarding it directly. (CVE-2022-49975)

  - In the Linux kernel, the following vulnerability has been resolved: ASoC: SOF: debug: Fix potential buffer
    overflow by snprintf() snprintf() returns the would-be-filled size when the string overflows the given
    buffer size, hence using this value may result in the buffer overflow (although it's unrealistic). This
    patch replaces with a safer version, scnprintf() for papering over such a potential issue.
    (CVE-2022-50051)

  - In the Linux kernel, the following vulnerability has been resolved: x86/alternatives: Disable KASAN in
    apply_alternatives() Fei has reported that KASAN triggers during apply_alternatives() on a 5-level paging
    machine: BUG: KASAN: out-of-bounds in rcu_is_watching() Read of size 4 at addr ff110003ee6419a0 by task
    swapper/0/0 ... __asan_load4() rcu_is_watching() trace_hardirqs_on() text_poke_early()
    apply_alternatives() ... On machines with 5-level paging, cpu_feature_enabled(X86_FEATURE_LA57) gets
    patched. It includes KASAN code, where KASAN_SHADOW_START depends on __VIRTUAL_MASK_SHIFT, which is
    defined with cpu_feature_enabled(). KASAN gets confused when apply_alternatives() patches the
    KASAN_SHADOW_START users. A test patch that makes KASAN_SHADOW_START static, by replacing
    __VIRTUAL_MASK_SHIFT with 56, works around the issue. Fix it for real by disabling KASAN while the kernel
    is patching alternatives. [ mingo: updated the changelog ] (CVE-2023-52504)

  - In the Linux kernel, the following vulnerability has been resolved: drm/amd: Fix UBSAN array-index-out-of-
    bounds for SMU7 For pptable structs that use flexible array sizes, use flexible arrays. (CVE-2023-52818)

  - In the Linux kernel, the following vulnerability has been resolved: nbd: defer config unlock in
    nbd_genl_connect There is one use-after-free warning when running NBD_CMD_CONNECT and NBD_CLEAR_SOCK:
    nbd_genl_connect nbd_alloc_and_init_config // config_refs=1 nbd_start_device // config_refs=2 set
    NBD_RT_HAS_CONFIG_REF open nbd // config_refs=3 recv_work done // config_refs=2 NBD_CLEAR_SOCK //
    config_refs=1 close nbd // config_refs=0 refcount_inc -> uaf ------------[ cut here ]------------
    refcount_t: addition on 0; use-after-free. WARNING: CPU: 24 PID: 1014 at lib/refcount.c:25
    refcount_warn_saturate+0x12e/0x290 nbd_genl_connect+0x16d0/0x1ab0 genl_family_rcv_msg_doit+0x1f3/0x310
    genl_rcv_msg+0x44a/0x790 The issue can be easily reproduced by adding a small delay before
    refcount_inc(&nbd->config_refs) in nbd_genl_connect(): mutex_unlock(&nbd->config_lock); if (!ret) {
    set_bit(NBD_RT_HAS_CONFIG_REF, &config->runtime_flags); + printk(before sleep\n); + mdelay(5 * 1000); +
    printk(after sleep\n); refcount_inc(&nbd->config_refs); nbd_connect_reply(info, nbd->index); }
    (CVE-2025-68366)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  # https://security.tuxcare.com/csaf/v2/els_os/centos-stream8els/advisories/2026/clsa-2026_1782375682.json
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?f1ff0a61");
  script_set_attribute(attribute:"see_also", value:"https://cve.tuxcare.com/els/releases/CLSA-2026:1782375682");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages based on the guidance in TuxCare advisory CENTOS-STREAM8:CLSA-2026:1782375682.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/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:L/AC:L/PR:L/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-2026-43027");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_set_attribute(attribute:"vendor_severity", value:"Important");

  script_set_attribute(attribute:"vuln_publication_date", value:"2021/07/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/06/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/01");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"CentOS 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_info2.nasl");
  script_require_keys("Host/OS/extended-third-party", "Host/local_checks_enabled", "Host/CentOS/release", "Host/CentOS/rpm-list");

  exit(0);
}
include('rpm2.inc');

var third_party_support = get_kb_item('Host/OS/extended-third-party');
if (empty_or_null(third_party_support) || third_party_support != 'TuxCare') exit(0, 'TuxCare support not enabled.');

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) || 'CentOS Linux' >!< os_product) audit(AUDIT_OS_NOT, 'CentOS Linux');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'CentOS Linux');
if (! preg(pattern:"^8([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'CentOS Linux 8', 'CentOS Linux ' + os_version);

if (!get_kb_item('Host/CentOS/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) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'CentOS Linux', cpu);


var constraints = [
  {
    'release': '8',
    'pkgs': [
      {'reference':'bpftool-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-core-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-cross-headers-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-core-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-devel-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-modules-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-modules-extra-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-debug-modules-internal-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-devel-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-headers-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-ipaclones-internal-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-modules-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-modules-extra-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-modules-internal-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-selftests-internal-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-libs-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-tools-libs-devel-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'perf-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-perf-4.18.0-553.6.1.el8_10.tuxcare.els24', 'cpu':'x86_64', 'el_string':'el8_10', 'rpm_spec_vers_cmp':TRUE}
    ]
  }
];

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 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;
  }
  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 &&
        ## (no known rpm to check OR known rpm_exists)
        (!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)
{
  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-core / kernel-cross-headers / etc');
}