What is CVE-2026-3303?

CVE-2026-3303 is a low-severity vulnerability in IBM Concert, classified under Permissive Cross-domain Policy with Untrusted Domains. CVSS score: 3.7/10. Published 2026-10-19.

How severe is CVE-2026-3303?

Low severity. CVSS v3 base score is 3.7 out of 10.

Vulnerability in IBM Concert

CVE-2026-3303

IBM Concert 1.0 through 3.0.0 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.

Published 2026-10-19 · last modified 2026-10-19.

CVSS v3 metric

CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

IBM Concert

Weakness classification (CWE)

CWE-942 — Permissive Cross-domain Policy with Untrusted Domains

References

www.ibm.com/support/pages/node/7292374 (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-3303?: CVE-2026-3303 is a low-severity vulnerability in IBM Concert, classified under Permissive Cross-domain Policy with Untrusted Domains. CVSS score: 3.7/10. Published 2026-10-19.
How severe is CVE-2026-3303?: Low severity. CVSS v3 base score is 3.7 out of 10.