Siemens Interniche IP-Stack Improper Verification of Source of a Communication Channel (CVE-2025-40820)

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

include('compat.inc');

if (description)
{
  script_id(505891);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/30");

  script_cve_id("CVE-2025-40820");

  script_name(english:"Siemens Interniche IP-Stack Improper Verification of Source of a Communication Channel (CVE-2025-40820)");

  script_set_attribute(attribute:"synopsis", value:
"The remote OT asset is affected by a vulnerability.");
  script_set_attribute(attribute:"description", value:
"Multiple Industrial products are affected by a vulnerability in the
Interniche IP-Stack. The affected products do not properly enforce
TCP sequence number validation in specific scenarios but accept
values within a broad range. This could allow an unauthenticated
remote attacker e.g. to interfere with connection setup, potentially
leading to a denial of service. The attack succeeds only if an
attacker can inject IP packets with spoofed addresses at precisely
timed moments, and it affects only TCP-based services.

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.");
  script_set_attribute(attribute:"see_also", value:"https://cert-portal.siemens.com/productcert/html/ssa-915282.html");
  script_set_attribute(attribute:"see_also", value:"https://www.cisa.gov/news-events/ics-advisories/icsa-25-352-05");
  script_set_attribute(attribute:"solution", value:
"The following text was originally created by the Cybersecurity and Infrastructure Security Agency (CISA). The original
can be found at CISA.gov.");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2025-40820");
  script_cwe_id(940);

  script_set_attribute(attribute:"vuln_publication_date", value:"2025/12/09");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/12/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/30");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:siemens:simatic_s7-1200_cpu_firmware:4.4.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:siemens:siplus_s7-1200_cpu_firmware:4.4.0");
  script_set_attribute(attribute:"generated_plugin", value:"former");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Tenable.ot");

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

  script_dependencies("tenable_ot_api_integration.nasl");
  script_require_keys("Tenable.ot/Siemens");

  exit(0);
}


include('tenable_ot_cve_funcs.inc');

get_kb_item_or_exit('Tenable.ot/Siemens');

var asset = tenable_ot::assets::get(vendor:'Siemens');

var vuln_cpes = {
    "cpe:/o:siemens:simatic_s7-1200_cpu_firmware:4.4.0" :
        {"versionEndExcluding" : "4.4.0", "family" : "S71200", "orderNumbers" : ['6ES7211-1BE40-0XB0', '6ES7211-1AE40-0XB0', '6ES7211-1HE40-0XB0', '6ES7212-1BE40-0XB0', '6ES7212-1AE40-0XB0', '6ES7212-1HE40-0XB0', '6ES7212-1AF40-0XB0', '6ES7212-1HF40-0XB0', '6ES7214-1BG40-0XB0', '6ES7214-1AG40-0XB0', '6ES7214-1HG40-0XB0', '6ES7214-1AF40-0XB0', '6ES7214-1HF40-0XB0', '6ES7215-1BG40-0XB0', '6ES7215-1AG40-0XB0', '6ES7215-1HG40-0XB0', '6ES7215-1AF40-0XB0', '6ES7215-1HF40-0XB0', '6ES7217-1AG40-0XB0']},
    "cpe:/o:siemens:siplus_s7-1200_cpu_firmware:4.4.0" :
        {"versionEndExcluding" : "4.4.0", "family" : "S71200", "orderNumbers" : ['6AG1212-1BE40-4XB0', '6AG1212-1HE40-2XB0', '6AG1212-1HE40-4XB0', '6AG1212-1BE40-2XB0', '6AG1212-1AE40-2XB0', '6AG1212-1AE40-4XB0', '6AG2212-1AE40-1XB0', '6AG1214-1BG40-5XB0', '6AG1214-1HG40-2XB0', '6AG1214-1BG40-2XB0', '6AG1214-1BG40-4XB0', '6AG1214-1AG40-2XB0', '6AG1214-1AG40-4XB0', '6AG1214-1AG40-5XB0', '6AG2214-1AG40-1XB0', '6AG1214-1HG40-4XB0', '6AG1214-1HG40-5XB0', '6AG1214-1AF40-5XB0', '6AG1214-1HF40-5XB0', '6AG1215-1BG40-4XB0', '6AG1215-1BG40-5XB0', '6AG1215-1AG40-2XB0', '6AG1215-1AG40-4XB0', '6AG1215-1HG40-2XB0', '6AG1215-1HG40-4XB0', '6AG1215-1HG40-5XB0', '6AG1215-1BG40-2XB0', '6AG1215-1AG40-5XB0', '6AG1215-1AF40-5XB0']}
};

tenable_ot::cve::compare_and_report(asset:asset, cpes:vuln_cpes, severity:SECURITY_HOLE);