[Japanese]

JVNDB-2019-000014

The installer of Microsoft Teams may insecurely load Dynamic Link Libraries

Overview

The installer of Microsoft Teams contains an issue with the DLL search path, which may lead to insecurely loading Dynamic Link Libraries (CWE-427).
Microsoft states that the root cause of this vulnerability is "Application Directory (App Dir) DLL planting", thus there is no plan to release any security updates to address this issue.

For details, refer to "Application Directory (App Dir) DLL planting" released by Microsoft.

Asuka Nakajima of NTT Secure Platform Laboratories reported this vulnerability to IPA.
JPCERT/CC coordinated with the developer under Information Security Early Warning Partnership.
CVSS Severity (What is CVSS?)

CVSS V3 Severity:
Base Metrics 7.8 (High) [IPA Score]
  • Attack Vector: Local
  • Attack Complexity: Low
  • Privileges Required: None
  • User Interaction: Required
  • Scope: Unchanged
  • Confidentiality Impact: High
  • Integrity Impact: High
  • Availability Impact: High
CVSS V2 Severity:
Base Metrics 6.8 (Medium) [IPA Score]
  • Access Vector: Network
  • Access Complexity: Medium
  • Authentication: None
  • Confidentiality Impact: Partial
  • Integrity Impact: Partial
  • Availability Impact: Partial
Affected Products


Microsoft Corporation
  • Microsoft Teams

Impact

Arbitrary code may be executed with the privilege of the user invoking the installer.
Solution

[Apply Workaround]
Applying the following workarounds may mitigate the impacts of this vulnerability.

*Save the installer into a newly created directory, and confirm there are no unrelated files in the directory then invoke the installer.
*Make sure there are no suspicious files in the directory where the installer is saved.
*If your organization uses shared directories to place installers for organizational operations, make sure that the shared directory is set read-only for non-administrative users.
Vendor Information

Microsoft Corporation
CWE (What is CWE?)

  1. No Mapping(CWE-Other) [IPA Evaluation]
CVE (What is CVE?)

  1. CVE-2019-5922
References

  1. JVN : JVN#79543573
  2. JVN : JVNTA#91240916
  3. National Vulnerability Database (NVD) : CVE-2019-5922
Revision History

  • [2019/04/02]
      Web page was published
  • [2019/09/26]
      References : Content was added