TencentOS Server 3: mingw-expat (TSSA-2023:0142)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Tencent Linux Security Advisory TSSA-2023:0142.
##

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

if (description)
{
  script_id(239666);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/11/22");

  script_cve_id(
    "CVE-2018-20843",
    "CVE-2022-25235",
    "CVE-2022-25236",
    "CVE-2022-25313",
    "CVE-2022-25314",
    "CVE-2022-25315",
    "CVE-2022-40674"
  );
  script_xref(name:"CEA-ID", value:"CEA-2021-0025");

  script_name(english:"TencentOS Server 3: mingw-expat (TSSA-2023:0142)");

  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-2023:0142 advisory.

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

      CVE-2022-40674:
      A vulnerability was found in expat. With this flaw, it is possible to create a situation in which
    parsing is suspended while substituting in an internal entity so that XML_ResumeParser directly uses the
    internalEntityProcessor as its processor. If the subsequent parse includes some unclosed tags, this will
    return without calling storeRawNames to ensure that the raw versions of the tag names are stored in memory
    other than the parse buffer itself. Issues occur if the parse buffer is changed or reallocated (for
    example, if processing a file line by line), problems occur. Using this vulnerability in the doContent
    function allows an attacker to triage a denial of service or potentially arbitrary code execution.

      CVE-2022-25236:
      A flaw was found in expat. Passing one or more namespace separator characters in the xmlns[:prefix]
    attribute values made expat send malformed tag names to the XML processor on top of expat. This issue
    causes arbitrary code execution depending on how unexpected cases are handled inside the XML processor.

      CVE-2022-25235:
      A flaw was found in expat. Passing malformed 2- and 3-byte UTF-8 sequences (for example, from start tag
    names) to the XML processing application on top of expat can lead to arbitrary code execution. This issue
    is dependent on how invalid UTF-8 is handled inside the XML processor.

      CVE-2022-25313:
      A flaw was found in expat. A stack exhaustion in doctype parsing could be triggered by a file with a
    large number of opening braces, resulting in a denial of service.

      CVE-2022-25314:
      An integer overflow flaw was found in expat. This issue affects the encoding name parameter at the
    parser creation time, which is often hard-coded (rather than user input), takes a value in the gigabytes
    to trigger, and on a 64-bit machine. This flaw can cause a denial of service.

      CVE-2022-25315:
      An integer overflow was found in expat. The issue occurs in storeRawNames() by abusing the m_buffer
    expansion logic to allow allocations very close to INT_MAX and out-of-bounds heap writes. This flaw can
    cause a denial of service or potentially arbitrary code execution.

      CVE-2018-20843:
      It was discovered that the setElementTypePrefix() function incorrectly extracted XML namespace
    prefixes. By tricking an application into processing a specially crafted XML file, an attacker could cause
    unusually high consumption of memory resources and possibly lead to a denial of service.

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-20230142.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:POC/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:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2022-25315");

  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:"2023/07/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2023/07/13");
  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:mingw-expat");
  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':'mingw32-expat-2.4.8-2.tl3', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'mingw32-expat-debuginfo-2.4.8-2.tl3', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'mingw32-expat-static-2.4.8-2.tl3', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'mingw64-expat-2.4.8-2.tl3', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'mingw64-expat-debuginfo-2.4.8-2.tl3', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'mingw64-expat-static-2.4.8-2.tl3', '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, 'mingw32-expat / mingw32-expat-debuginfo / mingw32-expat-static / etc');
}