What is CVE-2026-0977?

CVE-2026-0977 is a medium-severity vulnerability in IBM Cics Transaction Gateway, classified under Improper Access Control. CVSS score: 5.1/10. Published 2026-03-16.

How severe is CVE-2026-0977?

Medium severity. CVSS v3 base score is 5.1 out of 10.

Vulnerability in IBM Cics Transaction Gateway

CVE-2026-0977

IBM CICS Transaction Gateway for Multiplatforms 9.3 and 10.1 could allow a user to transfer or view files due to improper access controls.

Published 2026-03-16 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.1 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (9.4th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 9th percentile — 9.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

IBM Cics Transaction Gateway — versions 9.3, 10.1
IBM Cics Transaction Gateway For Multiplatforms — versions 9.3, 10.1

Weakness classification (CWE)

CWE-284 — Improper Access Control

References

www.ibm.com/support/pages/node/7263518 (vendor-advisory, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-0977?: CVE-2026-0977 is a medium-severity vulnerability in IBM Cics Transaction Gateway, classified under Improper Access Control. CVSS score: 5.1/10. Published 2026-03-16.
How severe is CVE-2026-0977?: Medium severity. CVSS v3 base score is 5.1 out of 10.