CVE-2026-16891: Vulnerabilities in IBM AIX and PowerVM VIOS

Published Aug 15, 2026
·
Updated

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to obtain sensitive information due to an out-of-bounds read.

Affected Software

10 affected components
IBM AIX<=7.2
IBM AIX<=7.3
IBM PowerVM VIOS<=4.1
IBM VIOS>=4.1.0<4.1.0.50
IBM VIOS>=4.1.1.0<4.1.1.30
IBM VIOS>=4.1.2.0<4.1.2.20
IBM AIX>=7.2.5<=7.2.5.212
IBM AIX>=7.3.2<=7.3.2.5
IBM AIX>=7.3.3<=7.3.3.2
IBM AIX>=7.3.4<=7.3.4.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade IBM PowerVM VIOS to a version that resolves this vulnerability.

    Fixed in 4.1.0.50
  2. Upgrade

    Upgrade IBM PowerVM VIOS to a version that resolves this vulnerability.

    Fixed in 4.1.1.30
  3. Upgrade

    Upgrade IBM PowerVM VIOS to a version that resolves this vulnerability.

    Fixed in 4.1.2.20
  4. Compensating control

    If applying AIX/VIOS patches using nimsh secure, follow the special nimsh secure steps because the protocol between master and client is updated to be more secure (as stated in the provided material).

  5. Operational

    For AIX SP/FP updates, reboot the LPAR to complete the SP/FP update (explicitly required in the provided post-update instructions).

  6. Operational

    For VIOS 4.1.0.50 and VIOS 4.1.1.30, perform the additional steps required to migrate to the latest Postgres15 after applying the specified 4.1.1.30 or 4.1.0.50 FPs (per the provided note and post-update instructions).

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·07:53 PM
Data Sourced
via MITRE·07:53 PM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·08:17 PM
RemedyDescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

Who can exploit this issue?

Exploitation requires local access to an affected IBM AIX or IBM PowerVM VIOS system. The available information does not indicate that it can be exploited remotely.

2

What is the potential impact?

A local attacker may obtain sensitive information through an out-of-bounds read.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203