CVE Vulnerabilities

CVE-2021-40904

Incorrect Default Permissions

Published: Mar 25, 2022 | Modified: Apr 04, 2022
CVSS 3.x
8.8
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS 2.x
6.8 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu
LOW

The web management console of CheckMK Raw Edition (versions 1.5.0 to 1.6.0) allows a misconfiguration of the web-app Dokuwiki (installed by default), which allows embedded php code. As a result, remote code execution is achieved. Successful exploitation requires access to the web management interface, either with valid credentials or with a hijacked session by a user with the role of administrator.

Weakness

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

Affected Software

Name Vendor Start Version End Version
Checkmk Tribe29 1.5.0 (including) 1.6.0 (excluding)
Check-mk Ubuntu bionic *
Check-mk Ubuntu esm-apps/bionic *
Check-mk Ubuntu esm-apps/xenial *
Check-mk Ubuntu trusty *
Check-mk Ubuntu upstream *
Check-mk Ubuntu xenial *

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