CVE-2026-6475
postgresql: PostgreSQL: Operating system account hijack via symlink following in pg_basebackup and pg_rewind
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · May 14, 2026
Updated · November 3, 2026
Description
A flaw was found in PostgreSQL. This vulnerability, related to symlink following in pg_basebackup (plain format) and pg_rewind, allows an origin superuser to overwrite local files. By exploiting this, an attacker could potentially hijack the operating system account. This attack has practical implications if specific actions are taken, such as moving files to a different virtual machine (VM) or snapshotting the VM, between the execution of these commands and the server's restart.
Statement
This MODERATE symlink following vulnerability in PostgreSQL's pg_basebackup and pg_rewind allows an origin superuser to overwrite local files. Exploitation requires local access, high privileges (superuser), and specific intermediate actions before server restart. Impact is high to confidentiality, integrity, and availability if exploited. Affects versions before 18.4, 17.10, 16.14, 15.18, and 14.23.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 6.7CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
CWE-59 · Improper Link Resolution Before File Access