CVE-2026-18408 HIGH

CVE-2026-18408: PostgreSQL psql \unrestrict lets superuser of pg_dump origin server execute arbitrary code in psql client

Vendor N/A
Product PostgreSQL
Weakness CWE-829 · Inclusion from untrusted sphere
Published August 13, 2026
Last update August 13, 2026

CVSS base score

8.8/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction Required
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

What the vulnerability does

01Description

Untrusted data inclusion in pg_dump in PostgreSQL allows a malicious superuser of the origin server to inject arbitrary code for restore-time execution as the client operating system account running psql to restore the dump, via psql \restrict meta-command input expansion. The fix for CVE-2025-8714 introduced \restrict and \unrestrict to block this attack, but \unrestrict itself was sufficient for an attack. pg_dumpall is also affected. pg_restore is affected when used to generate a plain-format dump. Non-core use of \restrict would be affected, but we've not identified non-core use. Versions before PostgreSQL 18.5, 17.11, 16.15, 15.19, and 14.24 are affected.

Key dates

02Disclosure timeline

August 13, 2026 CVE published
August 13, 2026 Record updated