Joomla! 3.8.8 - 3.9.16 Access Control Vulnerability

# SPDX-FileCopyrightText: 2020 Greenbone AG
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-only

CPE = "cpe:/a:joomla:joomla";

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.143745");
  script_version("2026-04-30T06:27:06+0000");
  script_tag(name:"last_modification", value:"2026-04-30 06:27:06 +0000 (Thu, 30 Apr 2026)");
  script_tag(name:"creation_date", value:"2020-04-22 03:06:53 +0000 (Wed, 22 Apr 2020)");
  script_tag(name:"cvss_base", value:"5.0");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:N/I:P/A:N");
  script_tag(name:"severity_vector", value:"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2020-04-29 18:01:00 +0000 (Wed, 29 Apr 2020)");

  script_cve_id("CVE-2020-11891");

  script_tag(name:"qod_type", value:"remote_banner");

  script_tag(name:"solution_type", value:"VendorFix");

  script_name("Joomla! 3.8.8 - 3.9.16 Access Control Vulnerability");

  script_category(ACT_GATHER_INFO);

  script_copyright("Copyright (C) 2020 Greenbone AG");
  script_family("Web application abuses");
  script_dependencies("joomla_http_detect.nasl");
  script_mandatory_keys("joomla/detected");

  script_tag(name:"summary", value:"Joomla! is prone to an access control vulnerability in com_users access level
  editing function.");

  script_tag(name:"vuldetect", value:"Checks if a vulnerable version is present on the target host.");

  script_tag(name:"insight", value:"Incorrect ACL checks in the access level section of com_users allow the
  unauthorized editing of usergroups.");

  script_tag(name:"affected", value:"Joomla! versions 3.8.8 - 3.9.16.");

  script_tag(name:"solution", value:"Update to version 3.9.17 or later.");

  script_xref(name:"URL", value:"https://developer.joomla.org/security-centre/809-20200401-core-incorrect-access-control-in-com-users-access-level-editing-function.html");

  exit(0);
}

include("host_details.inc");
include("version_func.inc");

if (!port = get_app_port(cpe: CPE))
  exit(0);

if (!infos = get_app_version_and_location(cpe: CPE, port: port, exit_no_version: TRUE))
  exit(0);

version = infos["version"];
location = infos["location"];

if (version_in_range(version: version, test_version: "3.8.8", test_version2: "3.9.16")) {
  report = report_fixed_ver(installed_version: version, fixed_version: "3.9.17", install_path: location);
  security_message(data: report, port: port);
  exit(0);
}

exit(99);