What is CVE-2026-16894?

CVE-2026-16894 is a critical-severity vulnerability in IBM Aix, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-08-19.

How severe is CVE-2026-16894?

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

Buffer overflow in IBM Aix

CVE-2026-16894

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a remote attacker to execute arbitrary code due to a stack buffer overflow.

Vulnerability class: Buffer Overflow

Published 2026-08-19 · last modified 2026-08-21.

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 (55.2th percentile), scored 2026-10-04.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 55.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

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

Affected products

IBM Aix — versions 7.2, 7.3
IBM Powervm Vios — versions 4.1
IBM Vios

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

www.ibm.com/support/pages/node/7283858 (vendor-advisory, Patch, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-16894?: CVE-2026-16894 is a critical-severity vulnerability in IBM Aix, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-08-19.
How severe is CVE-2026-16894?: Critical severity. CVSS v3 base score is 9.8 out of 10.