What is CVE-2026-18858?

CVE-2026-18858 is a low-severity vulnerability in IBM I, classified under Privilege Defined With Unsafe Actions. CVSS score: 3.3/10. Published 2026-09-04.

How severe is CVE-2026-18858?

Low severity. CVSS v3 base score is 3.3 out of 10.

Privilege escalation in IBM I

CVE-2026-18858

IBM i 7.6, and 7.5 could allow a local authenticated attacker to obtain information from a privileged file when using SSH.

Published 2026-09-04 · last modified 2026-09-08.

CVSS v3 metric

CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.001 (0.7th percentile), scored 2026-10-20.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 1st percentile — 0.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: 0.000

Affected products

IBM I — versions 7.5, 7.6

Weakness classification (CWE)

CWE-267 — Privilege Defined With Unsafe Actions

References

www.ibm.com/support/pages/node/7285938 (vendor-advisory, Patch, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-18858?: CVE-2026-18858 is a low-severity vulnerability in IBM I, classified under Privilege Defined With Unsafe Actions. CVSS score: 3.3/10. Published 2026-09-04.
How severe is CVE-2026-18858?: Low severity. CVSS v3 base score is 3.3 out of 10.