TencentOS Server 3: libyang (TSSA-2022:0076)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Tencent Linux Security Advisory TSSA-2022:0076.
##

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(239188);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/11/20");

  script_cve_id("CVE-2019-19333", "CVE-2019-19334");

  script_name(english:"TencentOS Server 3: libyang (TSSA-2022:0076)");

  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-2022:0076 advisory.

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

    CVE-2019-19333:
    In all versions of libyang before 1.0-r5, a stack-based buffer overflow was discovered in the way libyang
    parses YANG files with a leaf of type bits. An application that uses libyang to parse untrusted YANG
    files may be vulnerable to this flaw, which would allow an attacker to cause a denial of service or
    possibly gain code execution.

    CVE-2019-19334:
    In all versions of libyang before 1.0-r5, a stack-based buffer overflow was discovered in the way libyang
    parses YANG files with a leaf of type identityref. An application that uses libyang to parse untrusted
    YANG files may be vulnerable to this flaw, which would allow an attacker to cause a denial of service or
    possibly gain code execution.

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-20220076.xml");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  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: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-2019-19334");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2022/07/03");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/07/03");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/06/16");

  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:libyang");
  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 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':'libyang-0.16.105-3.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-0.16.105-3.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-cpp-0.16.105-3.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-cpp-0.16.105-3.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-cpp-debuginfo-0.16.105-3.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-cpp-debuginfo-0.16.105-3.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-cpp-devel-0.16.105-3.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-cpp-devel-0.16.105-3.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-debuginfo-0.16.105-3.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-debuginfo-0.16.105-3.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-debugsource-0.16.105-3.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-debugsource-0.16.105-3.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-devel-0.16.105-3.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-devel-0.16.105-3.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libyang-devel-doc-0.16.105-3.tl3.2', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-libyang-0.16.105-3.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-libyang-0.16.105-3.tl3.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-libyang-debuginfo-0.16.105-3.tl3.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-libyang-debuginfo-0.16.105-3.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, 'libyang / libyang-cpp / libyang-cpp-debuginfo / etc');
}