Vulnerabilities > CVE-2019-18196 - Untrusted Search Path vulnerability in Teamviewer

047910
CVSS 6.9 - MEDIUM
Attack vector
LOCAL
Attack complexity
MEDIUM
Privileges required
NONE
Confidentiality impact
COMPLETE
Integrity impact
COMPLETE
Availability impact
COMPLETE
local
teamviewer
CWE-426
nessus
NVD
Published: 2019-10-24
Updated: 2019-11-18

Summary

A DLL side loading vulnerability in the Windows Service in TeamViewer versions up to 11.0.133222 (fixed in 11.0.214397), 12.0.181268 (fixed in 12.0.214399), 13.2.36215 (fixed in 13.2.36216), and 14.6.4835 (fixed in 14.7.1965) on Windows could allow an attacker to perform code execution on a target system via a service restart where the DLL was previously installed with administrative privileges. Exploitation requires that an attacker be able to create a new file in the TeamViewer application directory; directory permissions restrict that by default.

Vulnerable Configurations

Part Description Count
Application
Teamviewer
47
OS
Microsoft
1

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Leveraging/Manipulating Configuration File Search Paths
    This attack loads a malicious resource into a program's standard path used to bootstrap and/or provide contextual information for a program like a path variable or classpath. J2EE applications and other component based applications that are built from multiple binaries can have very long list of dependencies to execute. If one of these libraries and/or references is controllable by the attacker then application controls can be circumvented by the attacker. A standard UNIX path looks similar to this If the attacker modifies the path variable to point to a locale that includes malicious resources then the user unwittingly can execute commands on the attackers' behalf: This is a form of usurping control of the program and the attack can be done on the classpath, database resources, or any other resources built from compound parts. At runtime detection and blocking of this attack is nearly impossible, because the configuration allows execution.

Nessus

NASL familyWindows
NASL idTEAMVIEWER_14_7_1965.NASL
descriptionA Dll sideloading vulnerability exist in TeamViewer 11 prior to 11.0.214397, TeamViewer 12 prior to 12.0.214399, TeamViewer 13 prior to 13.2.36216,TeamViewer 11 prior to 11.0.214397, on Windows could allow an attacker to perform code execution via service restart where the DLL was previously installed with administrative privileges in the target system.
last seen2020-04-30
modified2020-04-17
plugin id135709
published2020-04-17
reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/135709
titleTeamViewer Windows Service DLL Sideloading Vulnerability
code
#
# (C) Tenable Network Security, Inc.
#

include('compat.inc');

if (description)
{
  script_id(135709);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/04/23");

  script_cve_id("CVE-2019-18196");

  script_name(english:"TeamViewer Windows Service DLL Sideloading Vulnerability");

  script_set_attribute(attribute:"synopsis", value:
"The remote Windows host contains a program that is affected
by an arbitrary code execution vulnerability.");
  script_set_attribute(attribute:"description", value:
"A Dll sideloading vulnerability exist in 
TeamViewer 11 prior to 11.0.214397, TeamViewer 12 prior to 12.0.214399, 
TeamViewer 13 prior to 13.2.36216,TeamViewer 11 prior to 11.0.214397, on Windows could allow an attacker
to perform code execution via service restart where the DLL was previously installed with administrative 
privileges in the target system.");
  # https://community.teamviewer.com/t5/Announcements/Security-bulletin-CVE-2019-18196/td-p/74564
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?cc009a84");
  script_set_attribute(attribute:"solution", value:
"Upgrade for Teamviewer 11, upgrade to 11.0.214397 or later. For Teamviewer 12, upgrade to 12.0.214399 or later.
For Teamviewer 13, upgrade to 13.2.36216 or later. For Teamviewer 14, upgrade to 14.7.1965. 
Alternatively, apply the workarounds outlined in the vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:M/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-2019-18196");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_cwe_id(426);

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/10/22");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/10/22");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/04/17");

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

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

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

  script_dependencies("teamviewer_detect.nasl");
  script_require_keys("SMB/TeamViewer/Installed", "installed_sw/TeamViewer/");

  exit(0);
}

include('vcf.inc');

app_info = vcf::get_app_info(app:'TeamViewer');

constraints = [
  { "min_version" : "11.0.0", "fixed_version" : "11.0.214397" },
  { "min_version" : "12.0.0", "fixed_version" : "12.0.214399" },
  { "min_version" : "13.0.0", "fixed_version" : "13.2.36216" },
  { "min_version" : "14.0.0", "fixed_version" : "14.7.1965" }
];

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

References