CVE Vulnerabilities

CVE-2019-20889

Incorrect Default Permissions

Published: Jun 19, 2020 | Modified: Jun 23, 2020
CVSS 3.x
5.3
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CVSS 2.x
5 MEDIUM
AV:N/AC:L/Au:N/C:N/I:P/A:N
RedHat/V2
RedHat/V3
Ubuntu

An issue was discovered in Mattermost Server before 5.7, 5.6.3, 5.5.2, and 4.10.5. It mishandles permissions for user-access token creation.

Weakness

During installation, installed file permissions are set to allow anyone to modify those files.

Affected Software

Name Vendor Start Version End Version
Mattermost_server Mattermost 4.10.0 (including) 4.10.5 (excluding)
Mattermost_server Mattermost 5.5.0 (including) 5.5.2 (excluding)
Mattermost_server Mattermost 5.6.0 (including) 5.6.3 (excluding)
Mattermost_server Mattermost 5.7.0-rc1 (including) 5.7.0-rc1 (including)
Mattermost_server Mattermost 5.7.0-rc2 (including) 5.7.0-rc2 (including)
Mattermost_server Mattermost 5.7.0-rc3 (including) 5.7.0-rc3 (including)
Mattermost_server Mattermost 5.7.0-rc4 (including) 5.7.0-rc4 (including)
Mattermost_server Mattermost 5.7.0-rc5 (including) 5.7.0-rc5 (including)
Mattermost_server Mattermost 5.7.0-rc6 (including) 5.7.0-rc6 (including)

Potential Mitigations

  • Compartmentalize the system to have “safe” areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
  • Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

References