CVE Vulnerabilities

CVE-2016-8641

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

Published: Aug 01, 2018 | Modified: Feb 12, 2023
CVSS 3.x
7.8
HIGH
Source:
NVD
CVSS:3.0/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

A privilege escalation vulnerability was found in nagios 4.2.x that occurs in daemon-init.in when creating necessary files and insecurely changing the ownership afterwards. Its possible for the local attacker to create symbolic links before the files are to be created and possibly escalating the privileges with the ownership change.

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
Nagios Nagios 4.2.0 (including) 4.2.0 (including)
Nagios Nagios 4.2.1 (including) 4.2.1 (including)
Nagios Nagios 4.2.2 (including) 4.2.2 (including)
Nagios Nagios 4.2.3 (including) 4.2.3 (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