Vulnerabilities > CVE-2018-15442 - OS Command Injection vulnerability in Cisco Webex Meetings Desktop and Webex Productivity Tools

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-78
nessus
exploit available
metasploit

Summary

A vulnerability in the update service of Cisco Webex Meetings Desktop App for Windows could allow an authenticated, local attacker to execute arbitrary commands as a privileged user. The vulnerability is due to insufficient validation of user-supplied parameters. An attacker could exploit this vulnerability by invoking the update service command with a crafted argument. An exploit could allow the attacker to run arbitrary commands with SYSTEM user privileges. While the CVSS Attack Vector metric denotes the requirement for an attacker to have local access, administrators should be aware that in Active Directory deployments, the vulnerability could be exploited remotely by leveraging the operating system remote management tools.

Vulnerable Configurations

Part Description Count
Application
Cisco
2

Common Attack Pattern Enumeration and Classification (CAPEC)

  • 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.
  • Command Delimiters
    An attack of this type exploits a programs' vulnerabilities that allows an attacker's commands to be concatenated onto a legitimate command with the intent of targeting other resources such as the file system or database. The system that uses a filter or a blacklist input validation, as opposed to whitelist validation is vulnerable to an attacker who predicts delimiters (or combinations of delimiters) not present in the filter or blacklist. As with other injection attacks, the attacker uses the command delimiter payload as an entry point to tunnel through the application and activate additional attacks through SQL queries, shell commands, network scanning, and so on.
  • Exploiting Multiple Input Interpretation Layers
    An attacker supplies the target software with input data that contains sequences of special characters designed to bypass input validation logic. This exploit relies on the target making multiples passes over the input data and processing a "layer" of special characters with each pass. In this manner, the attacker can disguise input that would otherwise be rejected as invalid by concealing it with layers of special/escape characters that are stripped off by subsequent processing steps. The goal is to first discover cases where the input validation layer executes before one or more parsing layers. That is, user input may go through the following logic in an application: In such cases, the attacker will need to provide input that will pass through the input validator, but after passing through parser2, will be converted into something that the input validator was supposed to stop.
  • Argument Injection
    An attacker changes the behavior or state of a targeted application through injecting data or command syntax through the targets use of non-validated and non-filtered arguments of exposed services or methods.
  • 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.

Exploit-Db

  • fileexploits/windows/local/45696.rb
    idEDB-ID:45696
    last seen2018-11-30
    modified2018-10-25
    platformwindows
    port
    published2018-10-25
    reporterExploit-DB
    sourcehttps://www.exploit-db.com/download/45696
    titleWebEx - Local Service Permissions Exploit (Metasploit)
    typelocal
  • fileexploits/windows/remote/45695.rb
    idEDB-ID:45695
    last seen2018-11-30
    modified2018-10-25
    platformwindows
    port
    published2018-10-25
    reporterExploit-DB
    sourcehttps://www.exploit-db.com/download/45695
    titleWebExec - Authenticated User Code Execution (Metasploit)
    typeremote

Metasploit

Nessus

NASL familyCGI abuses
NASL idCISCO_WEBEX_MEETINGS_WIN_33_6_4.NASL
descriptionThe version of Cisco Webex Desktop App installed on the remote host is prior to 33.6.4, and thus, is affected by a command injection vulnerability.
last seen2020-05-15
modified2018-12-27
plugin id119888
published2018-12-27
reporterThis script is Copyright (C) 2018-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/119888
titleCisco Webex Meetings Desktop App < 33.6.4 Command Injection Vulnerability
code
#
# (C) Tenable Network Security, Inc.
#

include('compat.inc');

if (description)
{
  script_id(119888);
  script_version("1.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/05/13");

  script_cve_id("CVE-2018-15442");
  script_bugtraq_id(105734);

  script_name(english:"Cisco Webex Meetings Desktop App < 33.6.4 Command Injection Vulnerability");
  script_summary(english:"Checks the version of Cisco Webex Desktop App.");

  script_set_attribute(attribute:"synopsis", value:
"The remote host contains an application affected by a command
injection vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of Cisco Webex Desktop App installed on the remote host
is prior to 33.6.4, and thus, is affected by a command injection 
vulnerability.");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20181024-webex-injection
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?b3d7e129");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Cisco Webex Desktop App 33.6.4 or later.");
  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-2018-15442");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"exploit_framework_core", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'WebEx Local Service Permissions Exploit');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/10/24");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/11/27");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/12/27");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:cisco:webex_meetings");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"CGI abuses");

  script_copyright(english:"This script is Copyright (C) 2018-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("cisco_webex_meetings_win_installed.nbin");
  script_require_keys("installed_sw/Cisco Webex Meetings", "Settings/ParanoidReport");

  exit(0);
}

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

if (report_paranoia < 2) audit(AUDIT_PARANOID);

app_name = "Cisco Webex Meetings";

app_info = vcf::get_app_info(app:app_name);

vcf::check_granularity(app_info:app_info, sig_segments:3);

constraints = [
  { "min_version": "1.0.0",  "fixed_version" : "33.6.4" }
];

vcf::check_version_and_report(app_info:app_info, constraints:constraints, severity:SECURITY_HOLE);

Packetstorm