TencentOS Server 3: gstreamer1-plugins-bad-free (TSSA-2026:0632)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Tencent Linux Security Advisory TSSA-2026:0632.
##

include('compat.inc');

if (description)
{
  script_id(328410);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/20");

  script_cve_id("CVE-2026-52720", "CVE-2026-52722");

  script_name(english:"TencentOS Server 3: gstreamer1-plugins-bad-free (TSSA-2026:0632)");

  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-2026:0632 advisory.

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

    CVE-2026-52720:
    A heap buffer overflow vulnerability was found in GStreamer's librfb (RFB/VNC client). The rectangle
    bounds check incorrectly validates area rather than individual dimensions, allowing a malicious VNC server
    to send a rectangle that extends beyond the framebuffer. A remote attacker could set up a malicious VNC
    server and trick a user into connecting, resulting in an out-of-bounds heap write that could lead to code
    execution or a crash.

    CVE-2026-52722:
    A signed integer overflow vulnerability was found in GStreamer's VMnc decoder. A crafted VMnc stream with
    large cursor dimensions can overflow signed integer payload-size arithmetic, bypassing a length check and
    leading to out-of-bounds reads. A remote attacker could trick a user into opening a specially crafted VMnc
    file, potentially causing a crash or information disclosure.

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-20260632.xml");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/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:N/AC:L/PR:N/UI:R/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-2026-52720");

  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:"2026/06/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/07/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/20");

  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:gstreamer1-plugins-bad-free");
  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) 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':'gstreamer1-plugins-bad-free-1.16.1-8.tl3', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'gstreamer1-plugins-bad-free-1.16.1-8.tl3', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'gstreamer1-plugins-bad-free-debuginfo-1.16.1-8.tl3', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'gstreamer1-plugins-bad-free-debuginfo-1.16.1-8.tl3', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'gstreamer1-plugins-bad-free-debugsource-1.16.1-8.tl3', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'gstreamer1-plugins-bad-free-debugsource-1.16.1-8.tl3', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'gstreamer1-plugins-bad-free-devel-1.16.1-8.tl3', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'gstreamer1-plugins-bad-free-devel-1.16.1-8.tl3', '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, 'gstreamer1-plugins-bad-free / gstreamer1-plugins-bad-free-debuginfo / gstreamer1-plugins-bad-free-debugsource / etc');
}