PostgreSQL 14.x < 14.24 / 15.x < 15.19 / 16.x < 16.15 / 18.x < 18.6 amcheck Untrusted Search Path

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# Portions Copyright (C) 1996-2019, The PostgreSQL Global Development Group
# Portions Copyright (C) 1994, The Regents of the University of California
# Permission to use, copy, modify, and distribute this software and its documentation for any purpose, without fee, and without a written agreement is hereby granted, provided that the above copyright notice and this paragraph and the following two paragraphs appear in all copies.
# IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
# THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
##

include('compat.inc');

if (description)
{
  script_id(342123);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/09/02");

  script_cve_id("CVE-2026-14673");
  script_xref(name:"IAVB", value:"2026-B-0238");

  script_name(english:"PostgreSQL 14.x < 14.24 / 15.x < 15.19 / 16.x < 16.15 / 18.x < 18.6 amcheck Untrusted Search Path");

  script_set_attribute(attribute:"synopsis", value:
"The remote database server is affected by a privilege escalation vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of PostgreSQL installed on the remote host is 14 prior to 14.24, 15 prior to 15.19, 16 prior to 16.15, or 18
prior to 18.6. As such, it is potentially affected by a privilege escalation vulnerability:

  - Untrusted search path in PostgreSQL amcheck allows a grantee of amcheck function EXECUTE privilege to
    execute arbitrary functions as the owners of expression indexes that depend on the search path, via setting
    a hostile search path before calling the amcheck function. Within major versions 18, 16, 15, and 14, minor
    versions before PostgreSQL 18.6, 16.15, 15.19, and 14.24 are affected. PostgreSQL 17 is unaffected.
    (CVE-2026-14673)

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://www.postgresql.org/support/security/CVE-2026-14673");
  script_set_attribute(attribute:"solution", value:
"Upgrade to PostgreSQL 14.24 / 15.19 / 16.15 / 18.6 or later.");
  script_set_attribute(attribute:"agent", value:"all");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:M/C:P/I:P/A:N");
  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:L/I:L/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-14673");

  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:"2026/08/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/01");

  script_set_attribute(attribute:"plugin_type", value:"combined");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:postgresql:postgresql");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_set_attribute(attribute:"thorough_tests", value:"true");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Databases");

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

  script_dependencies("postgres_installed_windows.nbin", "postgres_installed_nix.nbin", "postgresql_version.nbin");
  script_require_ports("Services/postgresql", 5432, "installed_sw/PostgreSQL");

  exit(0);
}

include('vcf_extras_postgresql.inc');

var win_local = TRUE;
if (!get_kb_item('SMB/Registry/Enumerated'))
  win_local = FALSE;

var port = get_service(svc:'postgresql', default:5432);
var kb_base = 'database/' + port + '/postgresql/';
var kb_ver = NULL;
var kb_path = kb_base + 'version';
var ver = get_kb_item(kb_path);
if (!empty_or_null(ver)) kb_ver = kb_path;

var app_info = vcf::postgresql::get_app_info(app:'PostgreSQL', port:port, kb_ver:kb_ver, kb_base:kb_base, win_local:win_local);
vcf::check_granularity(app_info:app_info, sig_segments:2);

#  14.24 / 15.19 / 16.15 / 18.6 -- PostgreSQL 17 is unaffected
var constraints = [
  { 'min_version' : '14', 'fixed_version' : '14.24' },
  { 'min_version' : '15', 'fixed_version' : '15.19' },
  { 'min_version' : '16', 'fixed_version' : '16.15' },
  { 'min_version' : '18', 'max_version' : '18.4', 'fixed_version' : '18.6' }
];

vcf::postgresql::check_version_and_report(
  app_info:app_info,
  constraints:constraints,
  severity:SECURITY_WARNING
);