Siemens InsydeH2O SMM Privilege Escalation (CVE-2020-5953)

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

include('compat.inc');

if (description)
{
  script_id(501734);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/09/27");

  script_cve_id("CVE-2020-5953");

  script_name(english:"Siemens InsydeH2O SMM Privilege Escalation  (CVE-2020-5953)");

  script_set_attribute(attribute:"synopsis", value:
"The remote OT asset is affected by a vulnerability.");
  script_set_attribute(attribute:"description", value:
"A vulnerability exists in System Management Interrupt (SWSMI) handler
of InsydeH2O UEFI Firmware code located in SWSMI handler that
dereferences gRT (EFI_RUNTIME_SERVICES) pointer to call a GetVariable
service, which is located outside of SMRAM. This can result in code
execution in SMM (escalating privilege from ring 0 to ring -2).

Insyde BIOS is typically used in RUGGEDCOM APE products 
and some SIMATIC devices. Please refer to the vendor advisory for a 
precise list of models concerned.

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://www.insyde.com/security-pledge");
  script_set_attribute(attribute:"see_also", value:"https://www.insyde.com/products");
  script_set_attribute(attribute:"see_also", value:"https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf");
  script_set_attribute(attribute:"see_also", value:"https://security.netapp.com/advisory/ntap-20220222-0005/");
  script_set_attribute(attribute:"solution", value:
"Refer to the vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:M/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:L/AC:H/PR:H/UI:N/S:C/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-2020-5953");

  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:"2022/02/03");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/02/03");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/09/26");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:insyde:insydeh2o:5.12.09.0074");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:insyde:insydeh2o:5.23.04.0045");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:insyde:insydeh2o:5.23.45.0023");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:insyde:insydeh2o:5.33.15.0034");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:insyde:insydeh2o:5.34.03.0029");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:insyde:insydeh2o:5.42.03.0010");
  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) 2023 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:/a:insyde:insydeh2o:5.12.09.0074" :
        {"versionEndIncluding" : "5.12.09.0074", "versionStartIncluding" : "5.12.09.0074", "family" : "APE1808"},
    "cpe:/a:insyde:insydeh2o:5.23.04.0045" :
        {"versionEndIncluding" : "5.23.04.0045", "versionStartIncluding" : "5.23.04.0045", "family" : "APE1808"},
    "cpe:/a:insyde:insydeh2o:5.23.45.0023" :
        {"versionEndIncluding" : "5.23.45.0023", "versionStartIncluding" : "5.23.45.0023", "family" : "APE1808"},
    "cpe:/a:insyde:insydeh2o:5.33.15.0034" :
        {"versionEndIncluding" : "5.33.15.0034", "versionStartIncluding" : "5.33.15.0034", "family" : "APE1808"},
    "cpe:/a:insyde:insydeh2o:5.34.03.0029" :
        {"versionEndIncluding" : "5.34.03.0029", "versionStartIncluding" : "5.34.03.0029", "family" : "APE1808"},
    "cpe:/a:insyde:insydeh2o:5.42.03.0010" :
        {"versionEndIncluding" : "5.42.03.0010", "versionStartIncluding" : "5.42.03.0010", "family" : "APE1808"}
};

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