CVE-2026-16656: Vulnerabilities in IBM AIX and PowerVM VIOS

Q: Who is exposed to this vulnerability?

Systems running IBM AIX or IBM PowerVM VIOS are identified as affected. The issue can be exploited remotely, so network-reachable instances should be prioritized for triage.

Q: What level of access could an attacker obtain?

A remote attacker could gain root privileges due to improper authentication.

Published Aug 15, 2026

Updated

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a remote attacker to gain root privileges due to improper authentication.

Other sources

IBM AIX could allow a remote attacker to gain root privileges due to improper authentication.

— IBM

Affected Software

3 affected components

IBM AIX<=7.2

IBM AIX<=7.3

IBM PowerVM VIOS<=4.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade IBM PowerVM VIOS 4.1.0 to a version that resolves this vulnerability.
Fixed in 4.1.0.50Patch IJ5956508
Upgrade
Upgrade IBM PowerVM VIOS 4.1.1 to a version that resolves this vulnerability.
Fixed in 4.1.1.30Patch IJ5956408
Upgrade
Upgrade IBM PowerVM VIOS 4.1.2 to a version that resolves this vulnerability.
Fixed in 4.1.2.20Patch IJ5956308
Operational
Reboot the LPAR after completing the SP/FP update to complete the remediation.
Operational
For VIOS 4.1.0 and VIOS 4.1.1, perform the additional steps required to migrate to the latest Postgres15 after applying the 4.1.0.50 or 4.1.1.30 FPs.

Event History

Aug 15, 2026

CVE Published

via IBM·12:00 AM

Data Sourced

via IBM·12:00 AM

DescriptionAffected Software

Aug 19, 2026

CVE Published

via MITRE·02:55 PM

Data Sourced

via MITRE·02:55 PM

RemedyDescriptionSeverityWeakness

Parent advisories

This vulnerability appears in the following advisories.

IBM-7283858

Frequently Asked Questions

Who is exposed to this vulnerability?