AlmaLinux 9.2 [TuxCare] Security Update: gstreamer1-plugins-good / gstreamer1-plugins-good-gtk / etc Multiple Vulnerabilities (ALMALINUX9.2:CLSA-2026:1788272453)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(352119);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/01");

  script_cve_id(
    "CVE-2026-18295",
    "CVE-2026-18296",
    "CVE-2026-18298",
    "CVE-2026-18299",
    "CVE-2026-73433",
    "CVE-2026-73434"
  );
  script_xref(name:"CLSA", value:"2026:1788272453");

  script_name(english:"AlmaLinux 9.2 [TuxCare] Security Update: gstreamer1-plugins-good / gstreamer1-plugins-good-gtk / etc Multiple Vulnerabilities (ALMALINUX9.2:CLSA-2026:1788272453)");

  script_set_attribute(attribute:"synopsis", value:
"The AlmaLinux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The AlmaLinux 9.2 host has packages installed that are affected by multiple vulnerabilities as referenced in the TuxCare
ALMALINUX9.2:CLSA-2026:1788272453 advisory.

  - GStreamer MRF File Parsing Out-Of-Bounds Write Remote Code Execution Vulnerability. This vulnerability
    allows remote attackers to execute arbitrary code on affected installations of GStreamer. User interaction
    is required to exploit this vulnerability in that the target must visit a malicious page or open a
    malicious file. The specific flaw exists within the parsing of MRF files. The issue results from the lack
    of proper validation of user-supplied data, which can result in a write past the end of an allocated
    buffer. An attacker can leverage this vulnerability to execute code in the context of the current process.
    Was ZDI-CAN-29510. (CVE-2026-18295)

  - GStreamer MRF File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability. This
    vulnerability allows remote attackers to execute arbitrary code on affected installations of GStreamer.
    User interaction is required to exploit this vulnerability in that the target must visit a malicious page
    or open a malicious file. The specific flaw exists within the parsing of MRF files. The issue results from
    the lack of proper validation of the length of user-supplied data prior to copying it to a heap-based
    buffer. An attacker can leverage this vulnerability to execute code in the context of the current process.
    Was ZDI-CAN-29608. (CVE-2026-18296)

  - GStreamer PNG File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability. This
    vulnerability allows remote attackers to execute arbitrary code on affected installations of GStreamer.
    User interaction is required to exploit this vulnerability in that the target must visit a malicious page
    or open a malicious file. The specific flaw exists within the parsing of PNG files. The issue results from
    the lack of proper validation of the length of user-supplied data prior to copying it to a heap-based
    buffer. An attacker can leverage this vulnerability to execute code in the context of the current process.
    Was ZDI-CAN-29581. (CVE-2026-18298)

  - GStreamer rtpsbcdepay Use-After-Free Remote Code Execution Vulnerability. This vulnerability allows remote
    attackers to execute arbitrary code on affected installations of GStreamer. Interaction with this library
    is required to exploit this vulnerability but attack vectors may vary depending on the implementation. The
    specific flaw exists within the processing of RTP payload elements. The issue results from the lack of
    validating the existence of an object prior to performing operations on the object. An attacker can
    leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-29787.
    (CVE-2026-18299)

  - A flaw was found in GStreamer gst-plugins-good (avidemux). When parsing FUJIFILM metadata in an AVI strd
    chunk, gst_avi_demux_parse_strd() decrements a remaining-length counter by fixed offsets (98 and 10 bytes)
    without verifying sufficient data remains. For crafted strd payloads of exactly 106 or 107 bytes, the
    counter underflows to a very large unsigned value, causing subsequent null-terminated string scanning to
    read far beyond the allocated heap buffer. Date-format normalization may also write beyond the buffer end.
    Confirmed impacts include heap out-of-bounds read, out-of-bounds write, heap information disclosure
    (adjacent data appearing in parsed metadata), and application crash/denial of service. The avidemux
    element is auto-plugged by playbin, decodebin, and gst-discoverer, so opening or previewing a crafted AVI
    is sufficient to trigger the issue. Fixed upstream in gst-plugins-good 1.28.6 (GStreamer-SA-2026-0072).
    (CVE-2026-73433)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  # https://security.tuxcare.com/csaf/v2/els_os/almalinux9.2esu/advisories/2026/clsa-2026_1788272453.json
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?13dd9589");
  script_set_attribute(attribute:"see_also", value:"https://cve.tuxcare.com/els/releases/CLSA-2026:1788272453");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages based on the guidance in TuxCare advisory ALMALINUX9.2:CLSA-2026:1788272453.");
  script_set_cvss_base_vector("CVSS2#AV:L/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:L/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-2026-18299");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/08/12");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/09/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/30");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Alma 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_info2.nasl");
  script_require_keys("Host/OS/extended-third-party", "Host/local_checks_enabled", "Host/AlmaLinux/release", "Host/AlmaLinux/rpm-list", "Host/cpu");

  exit(0);
}
include('rpm2.inc');

var third_party_support = get_kb_item('Host/OS/extended-third-party');
if (empty_or_null(third_party_support) || third_party_support != 'TuxCare') exit(0, 'TuxCare support not enabled.');

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) || 'AlmaLinux' >!< os_product) audit(AUDIT_OS_NOT, 'AlmaLinux');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'AlmaLinux');
if (! preg(pattern:"^9.2([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'AlmaLinux 9.2', 'AlmaLinux ' + os_version);

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

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if (cpu !~ "^i[3-6]86$" && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'AlmaLinux', cpu);


var constraints = [
  {
    'release': '9',
    'sp': '2',
    'pkgs': [
      {'reference':'gstreamer1-plugins-good-1.18.4-6.el9.tuxcare.els20', 'sp':'2', 'cpu':'i686', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'gstreamer1-plugins-good-1.18.4-6.el9.tuxcare.els20', 'sp':'2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'gstreamer1-plugins-good-gtk-1.18.4-6.el9.tuxcare.els20', 'sp':'2', 'cpu':'i686', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'gstreamer1-plugins-good-gtk-1.18.4-6.el9.tuxcare.els20', 'sp':'2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'gstreamer1-plugins-good-qt-1.18.4-6.el9.tuxcare.els20', 'sp':'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, 'gstreamer1-plugins-good / gstreamer1-plugins-good-gtk / etc');
}