What is CVE-2026-17278?

CVE-2026-17278 is a critical-severity vulnerability in IBM API Connect, classified under Authentication Bypass by Spoofing. CVSS score: 9.8/10. Published 2026-11-07.

How severe is CVE-2026-17278?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in IBM API Connect

CVE-2026-17278

IBM API Connect 12.1.0.0 through 12.1.1.2 could allow a remote attacker to gain unauthorized access to sensitive API catalog and runtime configuration data due to improper authentication. Information supplied by the client is not sufficiently verified, which could allow a caller to appear as a trusted party.

Published 2026-11-07 · last modified 2026-11-07.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.007 (54.3th percentile), scored 2026-11-09.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 54th percentile — 54.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

The 30-day trend appears once there are two daily scores.

Affected products

IBM API Connect

Weakness classification (CWE)

CWE-290 — Authentication Bypass by Spoofing

References

www.ibm.com/support/pages/node/7295635 (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-17278?: CVE-2026-17278 is a critical-severity vulnerability in IBM API Connect, classified under Authentication Bypass by Spoofing. CVSS score: 9.8/10. Published 2026-11-07.
How severe is CVE-2026-17278?: Critical severity. CVSS v3 base score is 9.8 out of 10.