Published May 14, 2026Sources checked Nov 12, 2026
8.8HIGHCVSS out of 10
What this means
Review the available evidence
CVE-2026-6638 and is rated High severity with a CVSS score of 8.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
What to do next
Remediation and response
Microsoft Security Response Center guidance
Vendor revision: May 17, 2026
CBL-Mariner Releases
Vendor-listed releases
16.14-1
CISA KEVNot listedBased on the latest collected catalog
EPSS0.2%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2026-6638?
SQL injection in PostgreSQL logical replication ALTER SUBSCRIPTION ... REFRESH PUBLICATION allows a subscriber table creator to execute arbitrary SQL with the subscription's publication-side credentials.
The attack takes effect at the next REFRESH PUBLICATION. Within major versions 16, 17, and 18, minor versions before PostgreSQL 18.4, 17.10, and 16.14 are affected.