Privilege escalation in PostgreSQL

1) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU22785

Risk: Low

CVSSv3.1: 6.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-3466

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to pg_ctlcluster does not drop privileges before creating sockets and temporary directories outside "/var/run/postgresql". A local user can create arbitrary directories on the system during application startup or reload and elevate privileges on the system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

PostgreSQL: 9.4.0 - 12.0

External links

http://salsa.debian.org/postgresql/postgresql-common/commit/ec9d984b62ed79f61be97b786a9ff4381309979c
http://www.postgresql.org/about/news/1994/

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

The attacker would have to login to the system and perform certain actions in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.