RHEL 8 : tftp (RHSA-2026:78952)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Red Hat Security Advisory RHSA-2026:78952. The text
# itself is copyright (C) Red Hat, Inc.
##

include('compat.inc');

if (description)
{
  script_id(364154);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/08");

  script_cve_id("CVE-2026-85234");
  script_xref(name:"RHSA", value:"2026:78952");

  script_name(english:"RHEL 8 : tftp (RHSA-2026:78952)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Red Hat host is missing a security update for tftp.");
  script_set_attribute(attribute:"description", value:
"The remote Redhat Enterprise Linux 8 host has packages installed that are affected by a vulnerability as referenced in
the RHSA-2026:78952 advisory.

    The Trivial File Transfer Protocol (TFTP) is typically used only for booting diskless workstations. The
    tftp packages include the tftp and tftp-server subpackages. The tftp subpackage provides the user
    interface for TFTP and the tftp-server subpackage provides the server. This allows users to transfer files
    to and from a remote machine.

    Security Fix(es):

    * tftp: tftp-hpa: Denial of Service due to out-of-bounds read/write in remap engine (CVE-2026-85234)

    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 this issue 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/#moderate");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2460997");
  # https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_78952.json
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?695d22e7");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/errata/RHSA-2026:78952");
  script_set_attribute(attribute:"solution", value:
"Update the RHEL tftp package based on the guidance in RHSA-2026:78952.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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-2026-85234");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(125);
  script_set_attribute(attribute:"vendor_severity", value:"Moderate");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/09/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/08");

  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:tftp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:tftp-server");
  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");
  script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list", "Host/cpu");

  exit(0);
}


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

var constraints = [
  {
    'release': '8',
    'repo_relative_urls': [
      'content/dist/rhel8/8.10/aarch64/appstream/debug',
      'content/dist/rhel8/8.10/aarch64/appstream/os',
      'content/dist/rhel8/8.10/aarch64/appstream/source/SRPMS',
      'content/dist/rhel8/8.10/ppc64le/appstream/debug',
      'content/dist/rhel8/8.10/ppc64le/appstream/os',
      'content/dist/rhel8/8.10/ppc64le/appstream/source/SRPMS',
      'content/dist/rhel8/8.10/s390x/appstream/debug',
      'content/dist/rhel8/8.10/s390x/appstream/os',
      'content/dist/rhel8/8.10/s390x/appstream/source/SRPMS',
      'content/dist/rhel8/8.10/x86_64/appstream/debug',
      'content/dist/rhel8/8.10/x86_64/appstream/os',
      'content/dist/rhel8/8.10/x86_64/appstream/source/SRPMS',
      'content/dist/rhel8/8.6/aarch64/appstream/debug',
      'content/dist/rhel8/8.6/aarch64/appstream/os',
      'content/dist/rhel8/8.6/aarch64/appstream/source/SRPMS',
      'content/dist/rhel8/8.6/ppc64le/appstream/debug',
      'content/dist/rhel8/8.6/ppc64le/appstream/os',
      'content/dist/rhel8/8.6/ppc64le/appstream/source/SRPMS',
      'content/dist/rhel8/8.6/s390x/appstream/debug',
      'content/dist/rhel8/8.6/s390x/appstream/os',
      'content/dist/rhel8/8.6/s390x/appstream/source/SRPMS',
      'content/dist/rhel8/8.6/x86_64/appstream/debug',
      'content/dist/rhel8/8.6/x86_64/appstream/os',
      'content/dist/rhel8/8.6/x86_64/appstream/source/SRPMS',
      'content/dist/rhel8/8.8/aarch64/appstream/debug',
      'content/dist/rhel8/8.8/aarch64/appstream/os',
      'content/dist/rhel8/8.8/aarch64/appstream/source/SRPMS',
      'content/dist/rhel8/8.8/ppc64le/appstream/debug',
      'content/dist/rhel8/8.8/ppc64le/appstream/os',
      'content/dist/rhel8/8.8/ppc64le/appstream/source/SRPMS',
      'content/dist/rhel8/8.8/s390x/appstream/debug',
      'content/dist/rhel8/8.8/s390x/appstream/os',
      'content/dist/rhel8/8.8/s390x/appstream/source/SRPMS',
      'content/dist/rhel8/8.8/x86_64/appstream/debug',
      'content/dist/rhel8/8.8/x86_64/appstream/os',
      'content/dist/rhel8/8.8/x86_64/appstream/source/SRPMS',
      'content/dist/rhel8/8.9/aarch64/appstream/debug',
      'content/dist/rhel8/8.9/aarch64/appstream/os',
      'content/dist/rhel8/8.9/aarch64/appstream/source/SRPMS',
      'content/dist/rhel8/8.9/ppc64le/appstream/debug',
      'content/dist/rhel8/8.9/ppc64le/appstream/os',
      'content/dist/rhel8/8.9/ppc64le/appstream/source/SRPMS',
      'content/dist/rhel8/8.9/s390x/appstream/debug',
      'content/dist/rhel8/8.9/s390x/appstream/os',
      'content/dist/rhel8/8.9/s390x/appstream/source/SRPMS',
      'content/dist/rhel8/8.9/x86_64/appstream/debug',
      'content/dist/rhel8/8.9/x86_64/appstream/os',
      'content/dist/rhel8/8.9/x86_64/appstream/source/SRPMS',
      'content/dist/rhel8/8/aarch64/appstream/debug',
      'content/dist/rhel8/8/aarch64/appstream/os',
      'content/dist/rhel8/8/aarch64/appstream/source/SRPMS',
      'content/dist/rhel8/8/ppc64le/appstream/debug',
      'content/dist/rhel8/8/ppc64le/appstream/os',
      'content/dist/rhel8/8/ppc64le/appstream/source/SRPMS',
      'content/dist/rhel8/8/s390x/appstream/debug',
      'content/dist/rhel8/8/s390x/appstream/os',
      'content/dist/rhel8/8/s390x/appstream/source/SRPMS',
      'content/dist/rhel8/8/x86_64/appstream/debug',
      'content/dist/rhel8/8/x86_64/appstream/os',
      'content/dist/rhel8/8/x86_64/appstream/source/SRPMS',
      'content/e6s/rhel8/8.10/aarch64/appstream/debug',
      'content/e6s/rhel8/8.10/aarch64/appstream/os',
      'content/e6s/rhel8/8.10/aarch64/appstream/source/SRPMS',
      'content/e6s/rhel8/8.10/ppc64le/appstream/debug',
      'content/e6s/rhel8/8.10/ppc64le/appstream/os',
      'content/e6s/rhel8/8.10/ppc64le/appstream/source/SRPMS',
      'content/e6s/rhel8/8.10/s390x/appstream/debug',
      'content/e6s/rhel8/8.10/s390x/appstream/os',
      'content/e6s/rhel8/8.10/s390x/appstream/source/SRPMS',
      'content/e6s/rhel8/8.10/x86_64/appstream/debug',
      'content/e6s/rhel8/8.10/x86_64/appstream/os',
      'content/e6s/rhel8/8.10/x86_64/appstream/source/SRPMS',
      'content/public/ubi/dist/ubi8/8/aarch64/appstream/debug',
      'content/public/ubi/dist/ubi8/8/aarch64/appstream/os',
      'content/public/ubi/dist/ubi8/8/aarch64/appstream/source/SRPMS',
      'content/public/ubi/dist/ubi8/8/ppc64le/appstream/debug',
      'content/public/ubi/dist/ubi8/8/ppc64le/appstream/os',
      'content/public/ubi/dist/ubi8/8/ppc64le/appstream/source/SRPMS',
      'content/public/ubi/dist/ubi8/8/s390x/appstream/debug',
      'content/public/ubi/dist/ubi8/8/s390x/appstream/os',
      'content/public/ubi/dist/ubi8/8/s390x/appstream/source/SRPMS',
      'content/public/ubi/dist/ubi8/8/x86_64/appstream/debug',
      'content/public/ubi/dist/ubi8/8/x86_64/appstream/os',
      'content/public/ubi/dist/ubi8/8/x86_64/appstream/source/SRPMS'
    ],
    'pkgs': [
      {'reference':'tftp-5.2-28.el8_10', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'tftp-server-5.2-28.el8_10', '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, 'tftp / tftp-server');
}