Siemens SIMATIC S7-1500, SIMATIC S7-1500 Software Controller and SIMATIC ET 200SP OpenController Improper Input Validation (CVE-2018-13805)

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
##

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(500173);
  script_version("1.7");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/09/04");

  script_cve_id("CVE-2018-13805");
  script_xref(name:"ICSA", value:"18-282-05");

  script_name(english:"Siemens SIMATIC S7-1500, SIMATIC S7-1500 Software Controller and SIMATIC ET 200SP OpenController Improper Input Validation (CVE-2018-13805)");

  script_set_attribute(attribute:"synopsis", value:
"The remote OT asset is affected by a vulnerability.");
  script_set_attribute(attribute:"description", value:
"A vulnerability has been identified in SIMATIC ET 200SP Open Controller (All versions >= V2.0 and < V2.1.6), SIMATIC
S7-1500 Software Controller (All versions >= V2.0 and < V2.5), SIMATIC S7-1500 incl. F (All versions >= V2.0 and <
V2.5). An attacker can cause a denial-of-service condition on the network stack by sending a large number of specially
crafted packets to the PLC. The PLC will lose its ability to communicate over the network. This vulnerability could be
exploited by an attacker with network access to the affected systems. Successful exploitation requires no privileges and
no user interaction. An attacker could use this vulnerability to compromise availability of the network connectivity. At
the time of advisory publication no public exploitation of this vulnerability was known.  

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/pdf/ssa-347726.pdf");
  script_set_attribute(attribute:"see_also", value:"https://www.cisa.gov/news-events/ics-advisories/icsa-18-282-05");
  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.

Siemens provides updates to address this vulnerability in these products and recommends users update to the new version.

- SIMATIC S7-1500 Software Controller: Update to v2.5 or newer:

https://support.industry.siemens.com/cs/us/en/view/109478528

- SIMATIC S7-1500 incl. F: Update to v2.5 or newer:

https://support.industry.siemens.com/cs/us/en/ps/13717/dl 

- SIMATIC ET-200SP Open Controller: Update to v2.1.6 or newer:

https://support.industry.siemens.com/cs/us/en/view/109759122 

Siemens has identified the following specific workarounds and mitigations users can apply to reduce the risk:

- Restrict network access to affected devices
- Apply cell-protection concept
- Apply defense-in-depth

As a general security measure, Siemens strongly recommends protecting network access to devices with appropriate
mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends configuring the
environment according to Siemens’ operational guidelines for industrial security
(https://www.siemens.com/cert/operational-guidelines-industrial-security), and following the recommendations in the
product manuals.

Additional information on Industrial Security by Siemens can be found at:

https://www.siemens.com/industrialsecurity

For more information on this vulnerability and associated software updates, please see Siemens security advisory
SSA-347726 on their website:

https://www.siemens.com/cert/advisories");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  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:N/UI:N/S:U/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-13805");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(400);

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/10/10");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/10/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/02/07");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:siemens:simatic_et_200sp_firmware");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:siemens:simatic_s7-1500_firmware");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:siemens:simatic_s7-1500f_firmware");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2022-2024 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_et_200sp_firmware" :
        {"versionStartIncluding" : "2.0", "family" : "ET200SP"},
    "cpe:/o:siemens:simatic_s7-1500_firmware" :
        {"versionEndExcluding" : "2.5", "versionStartIncluding" : "2.0", "family" : "S71500"},
    "cpe:/o:siemens:simatic_s7-1500f_firmware" :
        {"versionEndExcluding" : "2.5", "versionStartIncluding" : "2.0", "family" : "S71500"}
};

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