CVE Vulnerabilities

CVE-2019-18901

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

Published: Mar 02, 2020 | Modified: Nov 16, 2022
CVSS 3.x
5.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
CVSS 2.x
2.1 LOW
AV:L/AC:L/Au:N/C:N/I:P/A:N
RedHat/V2
RedHat/V3
Ubuntu
MEDIUM

A UNIX Symbolic Link (Symlink) Following vulnerability in the mysql-systemd-helper of the mariadb packaging of SUSE Linux Enterprise Server 12, SUSE Linux Enterprise Server 15 allows local attackers to change the permissions of arbitrary files to 0640. This issue affects: SUSE Linux Enterprise Server 12 mariadb versions prior to 10.2.31-3.25.1. SUSE Linux Enterprise Server 15 mariadb versions prior to 10.2.31-3.26.1.

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
Leap Opensuse 15.1 (including) 15.1 (including)
Linux_enterprise_server Suse 12 (including) 12 (including)
Linux_enterprise_server Suse 15 (including) 15 (including)
Mariadb-5.5 Ubuntu trusty *
Mysql-5.5 Ubuntu trusty *
Mysql-5.6 Ubuntu trusty *
Percona-xtradb-cluster-5.5 Ubuntu trusty *

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