Vulnerabilities > CVE-2019-1791 - Argument Injection or Modification vulnerability in Cisco Nx-Os

047910
CVSS 7.2 - HIGH
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
COMPLETE
Integrity impact
COMPLETE
Availability impact
COMPLETE
local
low complexity
cisco
CWE-88
nessus

Summary

A vulnerability in the CLI of Cisco NX-OS Software could allow an authenticated, local attacker with administrator credentials to execute arbitrary commands with elevated privileges on the underlying operating system of an affected device. The vulnerability is due to insufficient validation of arguments passed to certain CLI commands. An attacker could exploit this vulnerability by including malicious input as the argument of an affected command. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system with elevated privileges. An attacker would need valid administrator credentials to exploit this vulnerability.

Vulnerable Configurations

Part Description Count
OS
Cisco
496
Hardware
Cisco
128

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Try All Common Application Switches and Options
    An attacker attempts to invoke all common switches and options in the target application for the purpose of discovering weaknesses in the target. For example, in some applications, adding a --debug switch causes debugging information to be displayed, which can sometimes reveal sensitive processing or configuration information to an attacker. This attack differs from other forms of API abuse in that the attacker is blindly attempting to invoke options in the hope that one of them will work rather than specifically targeting a known option. Nonetheless, even if the attacker is familiar with the published options of a targeted application this attack method may still be fruitful as it might discover unpublicized functionality.
  • Using Meta-characters in E-mail Headers to Inject Malicious Payloads
    This type of attack involves an attacker leveraging meta-characters in email headers to inject improper behavior into email programs. Email software has become increasingly sophisticated and feature-rich. In addition, email applications are ubiquitous and connected directly to the Web making them ideal targets to launch and propagate attacks. As the user demand for new functionality in email applications grows, they become more like browsers with complex rendering and plug in routines. As more email functionality is included and abstracted from the user, this creates opportunities for attackers. Virtually all email applications do not list email header information by default, however the email header contains valuable attacker vectors for the attacker to exploit particularly if the behavior of the email client application is known. Meta-characters are hidden from the user, but can contain scripts, enumerations, probes, and other attacks against the user's system.
  • HTTP Parameter Pollution (HPP)
    An attacker overrides or adds HTTP GET/POST parameters by injecting query string delimiters. Via HPP it may be possible to override existing hardcoded HTTP parameters, modify the application behaviors, access and, potentially exploit, uncontrollable variables, and bypass input validation checkpoints and WAF rules.
  • OS Command Injection
    In this type of an attack, an adversary injects operating system commands into existing application functions. An application that uses untrusted input to build command strings is vulnerable. An adversary can leverage OS command injection in an application to elevate privileges, execute arbitrary commands and compromise the underlying operating system.

Nessus

NASL familyCISCO
NASL idCISCO-SA-20190515-NXOS-CMDINJ-1791.NASL
descriptionAccording to its self-reported version, Cisco NX-OS Software is affected by vulnerability in the CLI of Cisco NX-OS Software which allow an authenticated, local attacker with administrator credentials to execute arbitrary commands with elevated privileges on the underlying operating system of an affected device. The vulnerability is due to insufficient validation of arguments passed to certain CLI commands. An attacker could exploit this vulnerability by including malicious input as the argument of an affected command. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system with elevated privileges. An attacker would need valid administrator credentials to exploit this vulnerability. Please see the included Cisco BIDs and Cisco Security Advisory for more information
last seen2020-06-01
modified2020-06-02
plugin id128079
published2019-08-22
reporterThis script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/128079
titleCisco NX-OS Software Command Injection Vulnerability (CVE-2019-1791)
code
#TRUSTED 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
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(128079);
  script_version("1.6");
  script_cvs_date("Date: 2019/12/20");

  script_cve_id("CVE-2019-1791");
  script_bugtraq_id(108390);
  script_xref(name:"CISCO-BUG-ID", value:"CSCvj63270");
  script_xref(name:"CISCO-BUG-ID", value:"CSCvj63667");
  script_xref(name:"CISCO-BUG-ID", value:"CSCvj50873");
  script_xref(name:"CISCO-BUG-ID", value:"CSCvj50876");
  script_xref(name:"CISCO-BUG-ID", value:"CSCvj50889");
  script_xref(name:"CISCO-SA", value:"cisco-sa-20190515-nxos-cmdinj-1791");
  script_xref(name:"IAVA", value:"2019-A-0173");

  script_name(english:"Cisco NX-OS Software Command Injection Vulnerability (CVE-2019-1791)");
  script_summary(english:"Checks the version of Cisco NX-OS Software");

  script_set_attribute(attribute:"synopsis", value:
"The remote device is missing a vendor-supplied security patch");
  script_set_attribute(attribute:"description", value:
"According to its self-reported version, Cisco NX-OS Software is affected by vulnerability in the CLI of Cisco NX-OS
Software which allow an authenticated, local attacker with administrator credentials to execute arbitrary commands
with elevated privileges on the underlying operating system of an affected device. The vulnerability is due to
insufficient validation of arguments passed to certain CLI commands. An attacker could exploit this vulnerability
by including malicious input as the argument of an affected command. A successful exploit could allow the attacker
to execute arbitrary commands on the underlying operating system with elevated privileges. An attacker would need
valid administrator credentials to exploit this vulnerability.

Please see the included Cisco BIDs and Cisco Security Advisory for more information");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190515-nxos-cmdinj-1791
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?f8cefff9");
  script_set_attribute(attribute:"see_also", value:"https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvj63270");
  script_set_attribute(attribute:"see_also", value:"https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvj63667");
  script_set_attribute(attribute:"see_also", value:"https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvj50873");
  script_set_attribute(attribute:"see_also", value:"https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvj50876");
  script_set_attribute(attribute:"see_also", value:"https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvj50889");
  script_set_attribute(attribute:"solution", value:
"Upgrade to the relevant fixed version referenced in Cisco bug IDs CSCvj63270, CSCvj63667, CSCvj50873, CSCvj50876,
and CSCvj50889");
  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: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: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-2019-1791");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_cwe_id(77);

  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:"2019/08/22");

  script_set_attribute(attribute:"plugin_type", value:"combined");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:nx-os");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("cisco_nxos_version.nasl");
  script_require_keys("Host/Cisco/NX-OS/Version", "Host/Cisco/NX-OS/Model", "Host/Cisco/NX-OS/Device");

  exit(0);
}

include('audit.inc');
include('cisco_workarounds.inc');
include('ccf.inc');

product_info = cisco::get_product_info(name:'Cisco NX-OS Software');

if (
  (product_info.device == 'Nexus' && product_info.model !~ '^(3[056]|5[56]|60|7[07]|9[05])[0-9][0-9]') ||
  (product_info.device == 'MDS' && product_info.model !~ '^(90)[0-9][0-9]'))
  audit(AUDIT_HOST_NOT, 'affected');

version_list=make_list(
  '8.2(2)',
  '8.2(1)',
  '7.0(3)I7(5a)',
  '7.0(3)I7(5)',
  '7.0(3)I7(4)',
  '7.0(3)I7(3)',
  '7.0(3)I7(2)',
  '7.0(3)I7(1)',
  '7.0(3)I4(8z)',
  '7.0(3)I4(8b)',
  '7.0(3)I4(8a)',
  '7.0(3)I4(8)',
  '7.0(3)I4(7)',
  '7.0(3)I4(6)',
  '7.0(3)I4(5)',
  '7.0(3)I4(4)',
  '7.0(3)I4(3)',
  '7.0(3)I4(2)',
  '7.0(3)I4(1)',
  '7.0(3)F3(4)',
  '7.0(3)F3(3c)',
  '7.0(3)F3(3b)',
  '7.0(3)F3(3a)',
  '7.0(3)F3(3)',
  '7.0(3)F3(2)',
  '7.0(3)F3(1)',
  '6.2(9c)',
  '6.2(9b)',
  '6.2(9a)',
  '6.2(9)',
  '6.2(8b)',
  '6.2(8a)',
  '6.2(8)',
  '6.2(7)',
  '6.2(6b)',
  '6.2(6a)',
  '6.2(6)',
  '6.2(5b)',
  '6.2(5a)',
  '6.2(5)',
  '6.2(3)',
  '6.2(2a)',
  '6.2(21)',
  '6.2(20a)',
  '6.2(20)',
  '6.2(2)',
  '6.2(19)',
  '6.2(18)',
  '6.2(17)',
  '6.2(16)',
  '6.2(15)',
  '6.2(14b)',
  '6.2(14a)',
  '6.2(14)',
  '6.2(13b)',
  '6.2(13a)',
  '6.2(13)',
  '6.2(12)',
  '6.2(11e)',
  '6.2(11d)',
  '6.2(11c)',
  '6.2(11b)',
  '6.2(11)',
  '6.2(10)',
  '6.2(1)',
  '6.0(2)A8(9)',
  '6.0(2)A8(8)',
  '6.0(2)A8(7b)',
  '6.0(2)A8(7a)',
  '6.0(2)A8(7)',
  '6.0(2)A8(6)',
  '6.0(2)A8(5)',
  '6.0(2)A8(4a)',
  '6.0(2)A8(4)',
  '6.0(2)A8(3)',
  '6.0(2)A8(2)',
  '6.0(2)A8(10a)',
  '6.0(2)A8(10)',
  '6.0(2)A8(1)'
);

workarounds = make_list(CISCO_WORKAROUNDS['no_workaround']);
workaround_params = make_list();

reporting = make_array(
  'port'     , 0,
  'severity' , SECURITY_HOLE,
  'version'  , product_info['version'],
  'bug_id'   , 'CSCvj63270, CSCvj63667, CSCvj50873, CSCvj50876, and CSCvj50889'
);

cisco::check_and_report(
  product_info:product_info,
  workarounds:workarounds,
  workaround_params:workaround_params,
  reporting:reporting,
  vuln_versions:version_list,
  switch_only:TRUE
);