CVE Vulnerabilities

CVE-2020-16144

Incorrect Default Permissions

Published: Feb 09, 2021 | Modified: Feb 18, 2021
CVSS 3.x
5.7
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:N
CVSS 2.x
3.5 LOW
AV:N/AC:M/Au:S/C:N/I:P/A:N
RedHat/V2
RedHat/V3
Ubuntu
MEDIUM

When using an object storage like S3 as the file store, when a user creates a public link to a folder where anonymous users can upload files, and another user uploads a virus the files antivirus app would detect the virus but fails to delete it due to permission issues. This affects the files_antivirus component versions before 0.15.2 for ownCloud.

Weakness

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

Affected Software

Name Vendor Start Version End Version
Files_antivirus Owncloud * 0.15.2 (excluding)
Owncloud Ubuntu trusty *

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