Buffer overflow in IBM Aix

CVE-2026-18842

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to gain elevated privileges due to an out-of-bounds write.

Vulnerability class: Buffer Overflow

CVSS v3 metric

CVSS v3 base score 8.4 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

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

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

psirt@us.ibm.com (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-18842?: CVE-2026-18842 is a high-severity vulnerability in IBM Aix, classified under Out-of-bounds Write. CVSS score: 8.4/10. Published 2026-08-20.
How severe is CVE-2026-18842?: High severity. CVSS v3 base score is 8.4 out of 10.