CVE-2026-18408

PostgreSQL psql \unrestrict lets superuser of pg_dump origin server execute arbitrary code in psql client

Published Aug 13, 2026 CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed
Description
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 18.6, 17.11, 16.15, 15.19, and 14.24 are affected.

Remediation

Vendor Workaround

use "pg_restore --dbname" instead of restore methods that involve "psql"

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Debian DLA Debian DLA DLA-4740-1 postgresql-15 security update
Debian DSA Debian DSA DSA-6438-1 postgresql-17 security update
Ubuntu USN Ubuntu USN USN-8653-1 PostgreSQL vulnerabilities
History
Type Values Removed Values Added
Description 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. 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 18.6, 17.11, 16.15, 15.19, and 14.24 are affected.
Type Values Removed Values Added
CPEs cpe:2.3:a:postgresql:postgresql:*:*:*:*:*:*:*:*
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Postgresql
Postgresql postgresql
Vendors & Products Postgresql
Postgresql postgresql
Type Values Removed Values Added
Description 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.
Title PostgreSQL psql \unrestrict lets superuser of pg_dump origin server execute arbitrary code in psql client
Weaknesses CWE-829
References
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
PostgreSQL
Published
Updated
Aug 29, 2026, 11:07 PM
Reserved
Jul 30, 2026, 4:28 PM
Status
Modified
Published
Aug 13, 2026, 1:17 PM
Modified
Aug 29, 2026, 11:17 PM