TencentOS Server 3: unbound (TSSA-2024:0083)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Tencent Linux Security Advisory TSSA-2024:0083.
##

include('compat.inc');

if (description)
{
  script_id(276323);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/03/11");

  script_cve_id("CVE-2023-50387", "CVE-2023-50868");

  script_name(english:"TencentOS Server 3: unbound (TSSA-2024:0083)");

  script_set_attribute(attribute:"synopsis", value:
"The remote TencentOS Server 3 host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The version of Tencent Linux installed on the remote TencentOS Server 3 host is prior to tested version. It is,
therefore, affected by multiple vulnerabilities as referenced in the TSSA-2024:0083 advisory.

    Package updates are available for TencentOS Server 3 that fix the following vulnerabilities:

    CVE-2023-50387:
    A flaw was found in the bind9 package. Processing specially crafted responses coming from DNSSEC-signed
    zones can lead to uncontrolled CPU usage, leading to a Denial of Service in the DNSSEC-validating resolver
    side.

    CVE-2023-50868:
    A flaw was found in bind9. By flooding a DNSSEC resolver with responses coming from a DNSEC-signed zone
    using NSEC3, an attacker can lead the targeted resolver to a CPU exhaustion, further leading to a Denial
    of Service on the targeted host.

Tenable has extracted the preceding description block directly from the Tencent 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://mirrors.tencent.com/tlinux/errata/tssa-20240083.xml");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  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:POC/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:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2023-50868");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2024/02/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2024/02/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/11/20");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:tencent:tencentos_server:3");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:tencent:tencentos_server:unbound");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2025-2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info2.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/etc/os-release", "Host/TencentOS/rpm-list", "Host/cpu");

  exit(0);
}


include('rpm2.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) || 'TencentOS' >!< os_product) audit(AUDIT_OS_NOT, 'TencentOS');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'TencentOS');
if (! preg(pattern:"^3([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'TencentOS 3.x', 'TencentOS ' + os_version);

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

var constraints = [
  {
    'release': '3',
    'pkgs': [
      {'reference':'python3-unbound-1.16.2-5.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-unbound-1.16.2-5.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-unbound-debuginfo-1.16.2-5.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-unbound-debuginfo-1.16.2-5.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-1.16.2-5.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-1.16.2-5.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-debuginfo-1.16.2-5.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-debuginfo-1.16.2-5.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-debugsource-1.16.2-5.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-debugsource-1.16.2-5.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-devel-1.16.2-5.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-devel-1.16.2-5.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-libs-1.16.2-5.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-libs-1.16.2-5.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-libs-debuginfo-1.16.2-5.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'unbound-libs-debuginfo-1.16.2-5.tl3.2', 'cpu':'x86_64', '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_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, 'python3-unbound / python3-unbound-debuginfo / unbound / etc');
}