CVE Vulnerabilities

CVE-2021-30463

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

Published: Apr 08, 2021 | Modified: Apr 14, 2021
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
7.2 HIGH
AV:L/AC:L/Au:N/C:C/I:C/A:C
RedHat/V2
RedHat/V3
Ubuntu

VestaCP through 0.9.8-24 allows attackers to gain privileges by creating symlinks to files for which they lack permissions. After reading the RKEY value from user.conf under the /usr/local/vesta/data/users/admin directory, the admin password can be changed via a /reset/?action=confirm&user=admin&code= URI. This occurs because chmod is used unsafely.

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
Control_panel Vestacp * 0.9.8-24 (including)

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