Out-of-bounds Read in IBM I

CVE-2026-81858

IBM i 7.3, 7.4, 7.5, and 7.6 could allow a remote authenticated attacker to cause a denial of service and obtain information due to an out-of-bounds read in the File Server.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L.

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 I — versions 7.3, 7.4, 7.5

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-81858?
CVE-2026-81858 is a medium-severity vulnerability in IBM I, classified under Out-of-bounds Read. CVSS score: 5.4/10. Published 2026-10-13.
How severe is CVE-2026-81858?
Medium severity. CVSS v3 base score is 5.4 out of 10.