Siemens SIMATIC S7-1500 TM MFP Use After Free (CVE-2026-28387)

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

include('compat.inc');

if (description)
{
  script_id(505452);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/17");

  script_cve_id("CVE-2026-28387");
  script_xref(name:"ICSA", value:"26-134-10");

  script_name(english:"Siemens SIMATIC S7-1500 TM MFP Use After Free (CVE-2026-28387)");

  script_set_attribute(attribute:"synopsis", value:
"The remote OT asset is affected by a vulnerability.");
  script_set_attribute(attribute:"description", value:
"Issue summary: An uncommon configuration of clients performing DANE
TLSA-based server authentication, when paired with uncommon server
DANE TLSA records, may result in a use-after-free and/or double-free
on the client side.  Impact summary: A use after free can have a range
of potential consequences such as the corruption of valid data,
crashes or execution of arbitrary code.  However, the issue only
affects clients that make use of TLSA records with both the PKIX-
TA(0/PKIX-EE(1) certificate usages and the DANE-TA(2) certificate
usage.  By far the most common deployment of DANE is in SMTP MTAs for
which RFC7672 recommends that clients treat as 'unusable' any TLSA
records that have the PKIX certificate usages.  These SMTP (or other
similar) clients are not vulnerable to this issue.  Conversely, any
clients that support only the PKIX usages, and ignore the DANE-TA(2)
usage are also not vulnerable.  The client would also need to be
communicating with a server that publishes a TLSA RRset with both
types of TLSA records.  No FIPS modules are affected by this issue,
the problem code is outside the FIPS module boundary.

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-032379.html");
  script_set_attribute(attribute:"see_also", value:"https://cert-portal.siemens.com/productcert/html/ssa-265688.html");
  script_set_attribute(attribute:"see_also", value:"https://support.industry.siemens.com/cs/ww/en/view/109814144/");
  script_set_attribute(attribute:"see_also", value:"https://www.cisa.gov/news-events/ics-advisories/ICSA-26-134-10");
  script_set_attribute(attribute:"solution", value:
"Refer to the vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/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-2026-28387");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(416);

  script_set_attribute(attribute:"vuln_publication_date", value:"2024/04/09");
  script_set_attribute(attribute:"patch_publication_date", value:"2024/04/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/06/18");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:siemens:simatic_s7-1500_tm_mfp");
  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_s7-1500_tm_mfp" :
        {"versionEndIncluding" : "1.1", "versionStartIncluding" : "1.1", "family" : "S71500", "orderNumbers": ["6ES7558-1AA00-0AB0"]}
};

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