Ruby REXML < 3.3.6 DoS vulnerability

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

include('compat.inc');

if (description)
{
  script_id(242630);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/03/23");

  script_cve_id("CVE-2024-43398");
  script_xref(name:"IAVB", value:"2024-B-0124-S");

  script_name(english:"Ruby REXML < 3.3.6 DoS vulnerability");

  script_set_attribute(attribute:"synopsis", value:
"The remote host has an application installed that is affected by a DoS vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of the REXML Ruby library installed on the remote host is prior to 3.3.6. It is, therefore, affected by a
DoS vulnerability. The vulnerability lies when it parses an XML that has many deep elements that have same local name attributes.

If you need to parse untrusted XMLs with tree parser API like REXML::Document.new, you may be impacted to this 
vulnerability. If you use other parser APIs such as stream parser API and SAX2 parser API, this vulnerability is not 
affected.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://github.com/ruby/rexml/security/advisories/GHSA-vmwr-mc7x-5vc3");
  script_set_attribute(attribute:"solution", value:
"Upgrade to REXML version 3.3.6 or later.");
  script_set_attribute(attribute:"agent", value:"all");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2024-43398");

  script_set_attribute(attribute:"vuln_publication_date", value:"2024/08/22");
  script_set_attribute(attribute:"patch_publication_date", value:"2024/08/22");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/07/23");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:ruby:rexml");
  script_set_attribute(attribute:"stig_severity", value:"II");
  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) 2025-2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ruby_modules_nix_installed.nbin", "ruby_gem_modules_macos_installed.nbin", "ruby_modules_win_installed.nbin");
  script_require_keys("Host/ruby/modules/enumerated");

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

var gem_name = 'rexml';

var app_info = ruby_gems::get_app_info(app:gem_name);

if (empty_or_null(app_info))
  audit(AUDIT_NOT_INST, gem_name);

vcf::check_all_backporting(app_info:app_info);

var constraints = [
  {'fixed_version': '3.3.6'}
];

vcf::check_version_and_report(app_info:app_info, constraints:constraints, severity:SECURITY_HOLE);