CVE Vulnerabilities

CVE-2016-6664

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

Published: Dec 13, 2016 | Modified: Jan 24, 2023
CVSS 3.x
7
HIGH
Source:
NVD
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
6.9 MEDIUM
AV:L/AC:M/Au:N/C:C/I:C/A:C
RedHat/V2
RedHat/V3
Ubuntu

mysqld_safe in Oracle MySQL through 5.5.51, 5.6.x through 5.6.32, and 5.7.x through 5.7.14; MariaDB; Percona Server before 5.5.51-38.2, 5.6.x before 5.6.32-78-1, and 5.7.x before 5.7.14-8; and Percona XtraDB Cluster before 5.5.41-37.0, 5.6.x before 5.6.32-25.17, and 5.7.x before 5.7.14-26.17, when using file-based logging, allows local users with access to the mysql account to gain root privileges via a symlink attack on error logs and possibly other files.

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
Mysql Oracle 5.5.0 (including) 5.5.51 (including)
Mysql Oracle 5.6.0 (including) 5.6.32 (including)
Mysql Oracle 5.7.0 (including) 5.7.14 (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