Elasticsearch 8.x < 8.19.20 / 9.0.x < 9.3.0 DoS (ESA-2026-47)

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

include('compat.inc');

if (description)
{
  script_id(344316);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/09/10");

  script_cve_id("CVE-2026-56143");

  script_name(english:"Elasticsearch 8.x < 8.19.20 / 9.0.x < 9.3.0 DoS (ESA-2026-47)");

  script_set_attribute(attribute:"synopsis", value:
"The remote host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The version of Elasticsearch installed on the remote host is 8.x prior to 8.19.20, or 9.0.x prior to 9.3.0. It is,
therefore, affected by a vulnerability as referenced in the ESA-2026-47 advisory.

  - Allocation of Resources Without Limits or Throttling (CWE-770) in Elasticsearch can lead to a denial of
    service via Excessive Allocation (CAPEC-130). A user with elevated privileges can submit a specially crafted
    request that causes excessive memory consumption, which may render the affected node unavailable.
    (CVE-2026-56143)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  # https://discuss.elastic.co/t/elasticsearch-8-19-20-9-3-0-security-update-esa-2026-47/390084
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?e53247a5");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Elasticsearch version 8.19.20 or 9.3.0 or later as appropriate for your release branch.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:M/C:N/I:N/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:H/UI:N/S:U/C:N/I:N/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-2026-56143");

  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:"2026/09/01");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/09/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/09");

  script_set_attribute(attribute:"plugin_type", value:"combined");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:elasticsearch:elasticsearch");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:elastic:elasticsearch");
  script_set_attribute(attribute:"thorough_tests", value:"true");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Misc.");

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("elasticsearch_detect.nbin", "elastic_elasticsearch_nix_installed.nbin");
  script_require_keys("installed_sw/Elasticsearch");

  exit(0);
}

include('vdf.inc');

# @tvdl-content
var vuln_data = {
  'metadata': {'spec_version': '1.0'},
  'checks': [
    {
      'product': {'name': 'Elasticsearch', 'type': 'app'},
      'check_algorithm': 'default',
      'constraints': [
        {'min_version': '8.0.0', 'fixed_version': '8.19.20'},
        {'min_version': '9.0.0', 'fixed_version': '9.3.0'}
      ]
    }
  ]
};

var vdf_result = vdf::check_and_report(vuln_data:vuln_data, severity:SECURITY_WARNING);
vdf::handle_check_and_report_errors(vdf_result:vdf_result);