TencentOS Server 2: xorg-x11-server (TSSA-2025:0558)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Tencent Linux Security Advisory TSSA-2025:0558.
##

include('compat.inc');

if (description)
{
  script_id(276085);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/11/20");

  script_cve_id(
    "CVE-2025-49175",
    "CVE-2025-49176",
    "CVE-2025-49178",
    "CVE-2025-49179",
    "CVE-2025-49180"
  );

  script_name(english:"TencentOS Server 2: xorg-x11-server (TSSA-2025:0558)");

  script_set_attribute(attribute:"synopsis", value:
"The remote TencentOS Server 2 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 2 host is prior to tested version. It is,
therefore, affected by multiple vulnerabilities as referenced in the TSSA-2025:0558 advisory.

    Package updates are available for TencentOS Server 2 that fix the following vulnerabilities:

    CVE-2025-49175:
    A flaw was found in the X Rendering extension's handling of animated cursors. If a client provides no
    cursors, the server assumes at least one is present, leading to an out-of-bounds read and potential crash.

    CVE-2025-49176:
    A flaw was found in the Big Requests extension. The request length is multiplied by 4 before checking
    against the maximum allowed size, potentially causing an integer overflow and bypassing the size check.

    CVE-2025-49178:
    A flaw was found in the X server's request handling. Non-zero 'bytes to ignore' in a client's request can
    cause the server to skip processing another client's request, potentially leading to a denial of service.

    CVE-2025-49179:
    A flaw was found in the X Record extension. The RecordSanityCheckRegisterClients function does not check
    for an integer overflow when computing request length, which allows a client to bypass length checks.

    CVE-2025-49180:
    A flaw was found in the RandR extension, where the RRChangeProviderProperty function does not properly
    validate input. This issue leads to an integer overflow when computing the total size to allocate.

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-20250558.xml");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  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-2025-49180");

  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:"2025/06/17");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/07/07");
  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:2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:tencent:tencentos_server:xorg-x11-server");
  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:"^2([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'TencentOS 2.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': '2',
    'pkgs': [
      {'reference':'xorg-x11-server-common-1.20.4-32.tl2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'xorg-x11-server-debuginfo-1.20.4-32.tl2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'xorg-x11-server-devel-1.20.4-32.tl2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'xorg-x11-server-source-1.20.4-32.tl2', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'xorg-x11-server-Xdmx-1.20.4-32.tl2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'xorg-x11-server-Xephyr-1.20.4-32.tl2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'xorg-x11-server-Xnest-1.20.4-32.tl2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'xorg-x11-server-Xorg-1.20.4-32.tl2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'xorg-x11-server-Xvfb-1.20.4-32.tl2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'xorg-x11-server-Xwayland-1.20.4-32.tl2', '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_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, 'xorg-x11-server-Xdmx / xorg-x11-server-Xephyr / xorg-x11-server-Xnest / etc');
}