CVE Vulnerabilities

CVE-2021-3987

Improper Access Control

Published: Nov 15, 2024 | Modified: Nov 19, 2024
CVSS 3.x
4.3
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
CVSS 2.x
RedHat/V2
RedHat/V3
Ubuntu

An improper access control vulnerability exists in janeczku/calibre-web. The affected version allows users without public shelf permissions to create public shelves. The vulnerability is due to the create_shelf method in shelf.py not verifying if the user has the necessary permissions to create a public shelf. This issue can lead to unauthorized actions being performed by users.

Weakness

The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

Affected Software

Name Vendor Start Version End Version
Calibre-web Janeczku * 0.6.15 (excluding)

Extended Description

Access control involves the use of several protection mechanisms such as:

When any mechanism is not applied or otherwise fails, attackers can compromise the security of the product by gaining privileges, reading sensitive information, executing commands, evading detection, etc. There are two distinct behaviors that can introduce access control weaknesses:

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