OpenLDAP <= 2.6.10 Heap Buffer Underflow Vulnerability

# SPDX-FileCopyrightText: 2026 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:openldap:openldap";

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.119268");
  script_version("2026-01-09T05:47:51+0000");
  script_tag(name:"last_modification", value:"2026-01-09 05:47:51 +0000 (Fri, 09 Jan 2026)");
  script_tag(name:"creation_date", value:"2026-01-08 16:12:25 +0000 (Thu, 08 Jan 2026)");
  script_tag(name:"cvss_base", value:"5.6");
  script_tag(name:"cvss_base_vector", value:"AV:L/AC:L/Au:N/C:P/I:N/A:C");

  script_cve_id("CVE-2026-22185");

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

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

  script_name("OpenLDAP <= 2.6.10 Heap Buffer Underflow Vulnerability");

  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2026 Greenbone AG");
  script_family("Buffer overflow");
  script_dependencies("gb_openldap_consolidation.nasl");
  script_mandatory_keys("openldap/detected");

  script_tag(name:"summary", value:"OpenLDAP is prone to a heap buffer underflow vulnerability.");

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

  script_tag(name:"insight", value:"OpenLDAP Lightning Memory-Mapped Database (LMDB) mdb_load
  contains a heap buffer underflow vulnerability in the readline() function. When processing
  malformed input, an unsigned offset calculation can underflow a heap pointer, resulting in an
  out-of-bounds read of one byte before the allocated heap buffer.");

  script_tag(name:"impact", value:"This may allow a local attacker to cause a denial of service and
  potentially disclose limited heap memory contents.");

  script_tag(name:"affected", value:"OpenLDAP versions 2.6.10 and prior.");

  script_tag(name:"solution", value:"No known solution is available as of 08th January, 2026.
  Information regarding this issue will be updated once solution details are available.");

  # nb: There are also two Full Disclosure mailing list postings linked on the CVE entry but these
  # seems to refer to MongoDB which internally somehow uses parts of OpenLDAP. As the ML postings
  # are not about OpenLDAP these links haven't been included here for now.
  script_xref(name:"URL", value:"https://www.vulncheck.com/advisories/openldap-lmdb-mdb-load-heap-buffer-underflow-in-readline");

  exit(0);
}

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

if (isnull(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_is_less_equal(version: version, test_version: "2.6.10")) {
  report = report_fixed_ver(installed_version: version, fixed_version: "None", install_path: location);
  security_message(port: port, data: report);
  exit(0);
}

exit(0);