CVE-2026-18221: IBM I

Critical severity, CVSS 9.8. EPSS: 0.3% chance of exploitation in the next 30 days.

IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to gain unauthorized access due to improper validation of client-supplied authentication parameters.

Affected products

• IBM I: version 7.3 only; version 7.4 only; version 7.5 only; version 7.6 only

Published 2026-09-04. Last modified 2026-09-08.