IBM DB2 Connect 9.7 < FP11 40481 / 10.1 < FP6 40480 / 10.5 < FP11 40479 / 11.1 < FP5 40478 / 11.5 < 11.5.5000.1587 Command Injection

##
# (C) Tenable Network Security, Inc.
##

include('compat.inc');

if (description)
{
  script_id(143552);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/01/07");

  script_cve_id("CVE-2020-4739");
  script_xref(name:"IAVB", value:"2020-B-0068-S");

  script_name(english:"IBM DB2 Connect 9.7 < FP11 40481 / 10.1 < FP6 40480 / 10.5 < FP11 40479 / 11.1 < FP5 40478 / 11.5 < 11.5.5000.1587 Command Injection");

  script_set_attribute(attribute:"synopsis", value:
"The remote database server is affected by a command injection vulnerability.");
  script_set_attribute(attribute:"description", value:
"A command injection vulnerability exists in IBM DB2 Connect due to a DLL search order hijacking vulnerability in Microsoft
Windows client. An unauthenticated, local attacker can exploit this, by placing a specially crafted file in a
compromised folder, to execute arbitrary commands.
  
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.ibm.com/support/pages/node/6370023");
  script_set_attribute(attribute:"solution", value:
"Apply the appropriate IBM DB2 Fix Pack or Special Build based on the most recent fix pack level for your branch.");
  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:L/PR:N/UI:R/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-2020-4739");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/11/18");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/11/18");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/12/08");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:ibm:db2_connect");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2020-2021 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("db2_and_db2_connect_installed.nbin");
  script_require_keys("SMB/db2_connect/Installed");

  exit(0);
}

include('install_func.inc');
include('db2_report_func.inc');

get_kb_item_or_exit('SMB/db2_connect/Installed');

app = 'DB2 Connect Server';
install = get_single_install(app_name:app, exit_if_unknown_ver:TRUE);
port = install['port'];
if (!port) port = 445;

version = kb_version = install['version'];

path = install['path'];

special_build = install['special_build'];
if (empty_or_null(special_build)) special_build = 'None';
if (special_build != 'None') kb_version += ' with Special Build ' + special_build;

fix_ver = NULL;
fix_build = NULL;

if (version =~ '^9\\.7\\.')
{
  fix_ver = '9.7.1100.352';
  fix_build = '40481';
}
else if (version =~ '^10\\.1\\.')
{
  fix_ver = '10.1.600.580';
  fix_build = '40480';
}
else if (version =~ '^10\\.5\\.')
{
  fix_ver = '10.5.1100.2866';
  fix_build = '40479';
}
else if (version =~ '^11\\.1\\.')
{
  fix_ver = '11.1.4050.859';
  fix_build = '40478';
}
else if (version =~ '^11\\.5\\.') {
  fix_ver = '11.5.5000.1587';
}
else {
  audit(AUDIT_INST_PATH_NOT_VULN, app, kb_version, path);
}

vuln = FALSE;
cmp = ver_compare(ver:version, fix:fix_ver, strict:FALSE);

# less than current fix pack                                      
if (cmp < 0)
  vuln = TRUE;
else if (cmp == 0 && !isnull(fix_build))
{
  # missing special build or less than current special build      
  if (special_build == 'None' || ver_compare(ver:special_build, fix:fix_build, strict:FALSE) < 0)
    vuln = TRUE;
}

if (!vuln)
  audit(AUDIT_INST_PATH_NOT_VULN, app, kb_version, path);

report_db2(
  severity          : SECURITY_WARNING,
  port              : port,
  product           : app,
  path              : path,
  installed_version : version,
  fixed_version     : fix_ver,
  special_installed : special_build,
  special_fix       : fix_build
);