Alibaba Cloud Linux 3 : 0205: gstreamer1-plugins-bad-free (ALINUX3-SA-2026:0205)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The package checks in this plugin were extracted from
# Alibaba Cloud Linux Security Advisory ALINUX3-SA-2026:0205.
##

include('compat.inc');

if (description)
{
  script_id(327257);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/16");

  script_cve_id(
    "CVE-2026-52718",
    "CVE-2026-52719",
    "CVE-2026-52720",
    "CVE-2026-52722"
  );

  script_name(english:"Alibaba Cloud Linux 3 : 0205: gstreamer1-plugins-bad-free (ALINUX3-SA-2026:0205)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Alibaba Cloud Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Alibaba Cloud Linux 3 host has packages installed that are affected by multiple vulnerabilities as referenced
in the ALINUX3-SA-2026:0205 advisory.

    Package updates are available for Alibaba Cloud Linux 3 that fix the following vulnerabilities:

    CVE-2026-52718:
    A denial of service vulnerability was found in GStreamer's AV1 codec parser in gst-plugins-bad. The
    gst_av1_parser_parse_tile_list_obu() function passes a byte count to a bit-reader API that expects a bit
    count, causing parser desynchronization. A remote attacker could trick a user into opening a specially
    crafted AV1 media file, triggering an assertion abort and causing the application to crash.

    CVE-2026-52719:
    An out-of-bounds read vulnerability was found in the VA JPEG decoder in GStreamer's gst-plugins-bad. The
    JPEG parser reads a segment length value from the bitstream without validating it against available data.
    A remote attacker could trick a user into opening a specially crafted JPEG file, causing downstream
    parsing to read beyond the provided input buffer, leading to a crash or potential information disclosure.

    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 Alibaba Cloud 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:"http://mirrors.aliyun.com/alinux/3/cve/alinux3-sa-20260205.xml");
  script_set_attribute(attribute:"solution", value:
"Update the affected gstreamer1-plugins-bad-free, gstreamer1-plugins-bad-free-devel and / or gstreamer1-plugins-bad-free-
libs 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:"2026/07/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/16");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:gstreamer1-plugins-bad-free");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:gstreamer1-plugins-bad-free-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:gstreamer1-plugins-bad-free-libs");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alibabacloud:alibaba_cloud_linux_3");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Alibaba Cloud Linux 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_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Alibaba/release", "Host/Alibaba/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) || 'Alibaba Cloud Linux' >!< os_product) audit(AUDIT_OS_NOT, 'Alibaba Cloud Linux');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'Alibaba Cloud Linux');
if (! preg(pattern:"^3([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'Alibaba Cloud Linux 3.x', 'Alibaba Cloud Linux ' + os_version);

if (!get_kb_item('Host/Alibaba/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('aarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Alibaba Cloud Linux', cpu);

var constraints = [
  {
    'release': '3',
    'pkgs': [
      {'reference':'gstreamer1-plugins-bad-free-1.22.12-7.0.1.al8.1', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'gstreamer1-plugins-bad-free-1.22.12-7.0.1.al8.1', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'gstreamer1-plugins-bad-free-devel-1.22.12-7.0.1.al8.1', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'gstreamer1-plugins-bad-free-devel-1.22.12-7.0.1.al8.1', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'gstreamer1-plugins-bad-free-libs-1.22.12-7.0.1.al8.1', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'gstreamer1-plugins-bad-free-libs-1.22.12-7.0.1.al8.1', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'}
    ]
  }
];

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-devel / etc');
}