CVE Vulnerabilities

CVE-2021-34408

Improper Link Resolution Before File Access ('Link Following')

Published: Sep 27, 2021 | Modified: Jul 12, 2022
CVSS 3.x
7.8
HIGH
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
4.6 MEDIUM
AV:L/AC:L/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu

The Zoom Client for Meetings for Windows in all versions before version 5.3.2 writes log files to a user writable directory as a privileged user during the installation or update of the client. This could allow for potential privilege escalation if a link was created between the user writable directory used and a non-user writable directory.

Weakness

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

Affected Software

Name Vendor Start Version End Version
Meetings Zoom * 5.3.2 (excluding)

Potential Mitigations

  • Follow the principle of least privilege when assigning access rights to entities in a software system.
  • Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

References