Cisco NX-OS Software SSH Key Information Disclosure (CVE-2019-1731)

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

include('compat.inc');

if (description)
{
  script_id(501352);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/07/26");

  script_cve_id("CVE-2019-1731");

  script_name(english:"Cisco NX-OS Software SSH Key Information Disclosure (CVE-2019-1731)");

  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 SSH CLI key management functionality of Cisco
NX-OS Software could allow an authenticated, local attacker to expose
a user's private SSH key to all authenticated users on the targeted
device. The attacker must authenticate with valid administrator device
credentials. The vulnerability is due to incomplete error handling if
a specific error type occurs during the SSH key export. An attacker
could exploit this vulnerability by authenticating to the device and
entering a crafted command at the CLI. A successful exploit could
allow the attacker to expose a user's private SSH key. In addition, a
similar type of error in the SSH key import could cause the
passphrase-protected private SSH key to be imported unintentionally.

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/108353");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190515-nxos-ssh-info
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?8f6c2fad");
  script_set_attribute(attribute:"solution", value:
"Refer to the vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:N");
  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:H/UI:N/S:U/C:H/I:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2019-1731");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_cwe_id(755);

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/05/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/05/15");
  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:6");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:nx-os:7");
  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%29i4%289%29" :
        {"versionEndExcluding" : "7.0%283%29i4%289%29", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:6.0%282%29a8%2810%29" :
        {"versionEndExcluding" : "6.0%282%29a8%2810%29", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:7.0%283%29i7%284%29" :
        {"versionEndExcluding" : "7.0%283%29i7%284%29", "versionStartIncluding" : "7.0%283%29i4", "family" : "NXOS"},
    "cpe:/o:cisco:nx-os:7.3%284%29n1%281%29" :
        {"versionEndExcluding" : "7.3%284%29n1%281%29", "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"}
};

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