Vulnerabilities > CVE-2013-5496 - Improper Input Validation vulnerability in Cisco Nx-Os

047910
CVSS 6.3 - MEDIUM
Attack vector
NETWORK
Attack complexity
MEDIUM
Privileges required
SINGLE
Confidentiality impact
NONE
Integrity impact
NONE
Availability impact
COMPLETE
network
cisco
CWE-20
nessus

Summary

Open Network Environment Platform (ONEP) in Cisco NX-OS allows remote authenticated users to cause a denial of service (network-element reload) via a crafted packet, aka Bug ID CSCui51551.

Vulnerable Configurations

Part Description Count
OS
Cisco
1

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Buffer Overflow via Environment Variables
    This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
  • Server Side Include (SSI) Injection
    An attacker can use Server Side Include (SSI) Injection to send code to a web application that then gets executed by the web server. Doing so enables the attacker to achieve similar results to Cross Site Scripting, viz., arbitrary code execution and information disclosure, albeit on a more limited scale, since the SSI directives are nowhere near as powerful as a full-fledged scripting language. Nonetheless, the attacker can conveniently gain access to sensitive files, such as password files, and execute shell commands.
  • Cross Zone Scripting
    An attacker is able to cause a victim to load content into their web-browser that bypasses security zone controls and gain access to increased privileges to execute scripting code or other web objects such as unsigned ActiveX controls or applets. This is a privilege elevation attack targeted at zone-based web-browser security. In a zone-based model, pages belong to one of a set of zones corresponding to the level of privilege assigned to that page. Pages in an untrusted zone would have a lesser level of access to the system and/or be restricted in the types of executable content it was allowed to invoke. In a cross-zone scripting attack, a page that should be assigned to a less privileged zone is granted the privileges of a more trusted zone. This can be accomplished by exploiting bugs in the browser, exploiting incorrect configuration in the zone controls, through a cross-site scripting attack that causes the attackers' content to be treated as coming from a more trusted page, or by leveraging some piece of system functionality that is accessible from both the trusted and less trusted zone. This attack differs from "Restful Privilege Escalation" in that the latter correlates to the inadequate securing of RESTful access methods (such as HTTP DELETE) on the server, while cross-zone scripting attacks the concept of security zones as implemented by a browser.
  • Cross Site Scripting through Log Files
    An attacker may leverage a system weakness where logs are susceptible to log injection to insert scripts into the system's logs. If these logs are later viewed by an administrator through a thin administrative interface and the log data is not properly HTML encoded before being written to the page, the attackers' scripts stored in the log will be executed in the administrative interface with potentially serious consequences. This attack pattern is really a combination of two other attack patterns: log injection and stored cross site scripting.
  • Command Line Execution through SQL Injection
    An attacker uses standard SQL injection methods to inject data into the command line for execution. This could be done directly through misuse of directives such as MSSQL_xp_cmdshell or indirectly through injection of data into the database that would be interpreted as shell commands. Sometime later, an unscrupulous backend application (or could be part of the functionality of the same application) fetches the injected data stored in the database and uses this data as command line arguments without performing proper validation. The malicious data escapes that data plane by spawning new commands to be executed on the host.

Nessus

NASL familyCISCO
NASL idCISCO-SN-CSCUI51551-NXOS.NASL
descriptionA vulnerability in the Open Network Environment Platform (ONEP) could allow an authenticated, remote attacker to cause the network element to reload. The vulnerability is due to insufficient pointer validation. An attacker could exploit this vulnerability by sending a crafted packet to an ONEP-enabled network element. Successful exploitation could allow the attacker to cause the network element to reload.
last seen2020-06-01
modified2020-06-02
plugin id70399
published2013-10-11
reporterThis script is Copyright (C) 2013-2019 Tenable Network Security, Inc.
sourcehttps://www.tenable.com/plugins/nessus/70399
titleCisco Open Network Environment Platform Unvalidated Pointer (CSCui51551)
code
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text in this plugin was extracted from Cisco
# Security Notice CVE-2013-1121.  The text itself is copyright (C)
# Cisco.
#

include("compat.inc");

if (description)
{
  script_id(70399);
  script_version("1.5");
  script_cvs_date("Date: 2019/10/29 10:38:39");

  script_cve_id("CVE-2013-5496");
  script_bugtraq_id(62403);
  script_xref(name:"CISCO-BUG-ID", value:"CSCui51551");

  script_name(english:"Cisco Open Network Environment Platform Unvalidated Pointer (CSCui51551)");
  script_summary(english:"Checks the NX-OS version.");

  script_set_attribute(attribute:"synopsis", value:"The remote device is missing a vendor-supplied security patch.");
  script_set_attribute(attribute:"description", value:
"A vulnerability in the Open Network Environment Platform (ONEP) could
allow an authenticated, remote attacker to cause the network element
to reload.

The vulnerability is due to insufficient pointer validation. An
attacker could exploit this vulnerability by sending a crafted packet
to an ONEP-enabled network element. Successful exploitation could
allow the attacker to cause the network element to reload.");
  # https://tools.cisco.com/security/center/viewAlert.x?alertId=30795
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?f77b5da1");
  script_set_attribute(attribute:"solution", value:"Apply the patch referenced in Cisco bug ID CSCui51551.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:S/C:N/I:N/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2013/09/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2013/09/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2013/10/11");

  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2013-2019 Tenable Network Security, Inc.");
  script_family(english:"CISCO");

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

  exit(0);
}

include("audit.inc");
include("cisco_func.inc");

device = get_kb_item_or_exit("Host/Cisco/NX-OS/Device");
model = get_kb_item_or_exit("Host/Cisco/NX-OS/Model");
version = get_kb_item_or_exit("Host/Cisco/NX-OS/Version");

# only affects nexus 3000 series systems
if (device != 'Nexus' || model !~ '^3[0-9][0-9][0-9]([^0-9]|$)') audit(AUDIT_HOST_NOT, "affected");

if (
 version == "6.0(2)U1(1)" ||
 version == "6.0(2)U1(2)"
)
{
  if (report_verbosity > 0)
  {
    report =
      '\n  Model             : ' + device + ' ' + model +
      '\n  Installed version : ' + version +
      '\n  Fixed version     : 6.0(2)U1(3)' +
      '\n';
    security_warning(port:0, extra:report);
  }
  else security_warning(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");