CVE-2026-18408: Untrusted data inclusion in pg_dump in PostgreSQL allows a malicious superuser of the origin server to inject

Routine

HIGH 8.8UPGRADE

CVE-2026-18408 is a high-severity flaw (CVSS 8.8) affecting postgresql. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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_res

Why this priority

High severity

A fixed release or distro patch exists.

Risk facts

CVSS score	8.8 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.4% (top 71%)
CISA exploited list	No
Weakness	CWE-829
Published	2026-08-13
Last modified	2026-08-29

Publisher (CNA): PostgreSQL · Vendor: postgresql

Last updated 2026-08-29 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-08-13 13:17 UTCPublished CVE record published
2026-08-29 23:17 UTCUpdated Record last modified

postgresql postgresql UPGRADE

Affected: >= 14.0 and < 14.24 · >= 15.0 and < 15.19 · >= 16.0 and < 16.15 · >= 17.0 and < 17.11 · >= 18.0 and < 18.5

Fixed in: 14.24, 15.19, 16.15, 17.11, 18.5

Safe to downgrade to: a release before 14.0

1. Check installed version

apt-cache policy postgresql || rpm -q postgresql || postgresql --version

2. UPGRADE to 14.24 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade postgresql

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade postgresql

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 14.0 (Debian / Ubuntu)

apt-cache madison postgresql sudo apt install postgresql=<VERSION_BEFORE_14.0> sudo apt-mark hold postgresql

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list postgresql sudo dnf downgrade postgresql-<VERSION_BEFORE_14.0> sudo dnf versionlock add postgresql

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-18408?

postgresql: upgrade to 14.24, 15.19, 16.15, 17.11, 18.5. Exact commands for each OS are on this page.

Is CVE-2026-18408 being exploited?

CVE-2026-18408 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-18408 affect?

CVE-2026-18408 affects postgresql. Severity is high (CVSS 8.8). 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 \restr

How urgent is CVE-2026-18408?

Priority 38/100. High severity

Software pages

PostgreSQL vulnerabilities

Related CVEs

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CVE-2026-6464 HIGH 8.1 UPGRADE Untrusted data inclusion in PostgreSQL psql COPY may allow a server administrator to elicit execution of data
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References

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