Buffer overflow in IBM I

CVE-2026-17218

IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to execute arbitrary code due to an out-of-bounds write.

Vulnerability class: Buffer Overflow

Published · last modified .

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: 0.008 (54.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 54.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-17218: held from 0.006 to 0.008.

EPSS over last 30 days · oldest: 0.006 · newest: 0.008 · change: +0.002

Affected products

  • IBM I — versions 7.6, 7.5, 7.4

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-17218?
CVE-2026-17218 is a critical-severity vulnerability in IBM I, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-08-12.
How severe is CVE-2026-17218?
Critical severity. CVSS v3 base score is 9.8 out of 10.