Cisco NX-OS Software Bash Shell Role-Based Access Control Bypass Privilege Escalation (CVE-2019-1593)

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

include('compat.inc');

if (description)
{
  script_id(501341);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/07/26");

  script_cve_id("CVE-2019-1593");

  script_name(english:"Cisco NX-OS Software Bash Shell Role-Based Access Control Bypass Privilege Escalation (CVE-2019-1593)");

  script_set_attribute(attribute:"synopsis", value:
"The remote OT asset is affected by a vulnerability.");
  script_set_attribute(attribute:"description", value:
"A vulnerability in the Bash shell implementation for Cisco NX-OS
Software could allow an authenticated, local attacker to escalate
their privilege level by executing commands authorized to other user
roles. The attacker must authenticate with valid user credentials. The
vulnerability is due to the incorrect implementation of a Bash shell
command that allows role-based access control (RBAC) to be bypassed.
An attacker could exploit this vulnerability by authenticating to the
device and entering a crafted command at the Bash prompt. A successful
exploit could allow the attacker to escalate their privilege level by
executing commands that should be restricted to other roles. For
example, a dev-ops user could escalate their privilege level to admin
with a successful exploit of this vulnerability.

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:"http://www.securityfocus.com/bid/107324");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190306-nx-os-bash-escal
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?b371e68a");
  script_set_attribute(attribute:"solution", value:
"Refer to the vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:F/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2019-1593");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/03/06");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/03/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/07/25");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:nx-os:13");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:nx-os:14");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:nx-os:7");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:nx-os:8");
  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/Cisco");

  exit(0);
}


include('tenable_ot_cve_funcs.inc');

get_kb_item_or_exit('Tenable.ot/Cisco');

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

var vuln_cpes = {
    "cpe:/o:cisco:nx-os:7.0%283%29i7%284%29" :
        {"versionEndExcluding" : "7.0%283%29i7%284%29", "versionStartIncluding" : "7.0%283%29", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:7.0%283%29i4%289%29" :
        {"versionEndExcluding" : "7.0%283%29i4%289%29", "versionStartIncluding" : "7.0%283%29i4", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:7.0%283%29f3%285%29" :
        {"versionEndExcluding" : "7.0%283%29f3%285%29", "versionStartIncluding" : "7.0%283%29", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:8.2%283%29" :
        {"versionEndExcluding" : "8.2%283%29", "versionStartIncluding" : "8.1", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:8.3%281%29" :
        {"versionEndExcluding" : "8.3%281%29", "versionStartIncluding" : "8.3", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:13.2%284d%29" :
        {"versionEndExcluding" : "13.2%284d%29", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:14.0%281h%29" :
        {"versionEndExcluding" : "14.0%281h%29", "versionStartIncluding" : "14.0", "family" : "NXOS"}
};

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