CVE-2025-27909: IBM Concert

Critical severity, CVSS 9.8. EPSS: 0.2% chance of exploitation in the next 30 days.

IBM Concert Software 1.0.0 through 1.1.0 uses cross-origin resource sharing (CORS) which could allow an attacker to carry out privileged actions as the domain name is not being limited to only trusted domains.

Affected products

• IBM Concert: from 1.0.0, before 2.0.0 (fixed in 2.0.0)

Published 2025-08-18. Last modified 2026-06-17.