CVE-2026-16991: Vulnerabilities in IBM AIX and PowerVM VIOS

Q: Which IBM products are identified as affected?

The affected software listed is IBM AIX and IBM PowerVM VIOS.

Q: Does an attacker need local access to exploit this issue?

Yes. The issue is described as requiring a local attacker, who could gain elevated privileges through improper handling of symbolic links.

Published Aug 15, 2026

Updated

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to gain elevated privileges due to improper handling of symbolic links.

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.

Upgrade
Upgrade IBM PowerVM VIOS 4.1.0 to a version that resolves this vulnerability.
Fixed in 4.1.0.50
Upgrade
Upgrade IBM PowerVM VIOS 4.1.1 to a version that resolves this vulnerability.
Fixed in 4.1.1.30
Upgrade
Upgrade IBM PowerVM VIOS 4.1.2 to a version that resolves this vulnerability.
Fixed in 4.1.2.20
Upgrade
Upgrade AIX 7.2 to a version that resolves this vulnerability.
Patch SP13key_w_apar
Operational
Reboot the LPAR is required to complete the SP/FP update.
Operational
For VIOS 4.1.0 and VIOS 4.1.1, after applying the 4.1.0.50 or 4.1.1.30 FPs, perform the additional steps required to migrate to the latest Postgres15.

Event History

Aug 15, 2026

CVE Published

via IBM·12:00 AM

Data Sourced

via IBM·12:00 AM

DescriptionAffected Software

Aug 20, 2026

CVE Published

via MITRE·09:47 PM

Data Sourced

via MITRE·09:47 PM

RemedyDescriptionSeverityWeakness

Data Sourced

via NVD·10:17 PM

RemedyDescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

IBM-7283858

Frequently Asked Questions

Which IBM products are identified as affected?

The affected software listed is IBM AIX and IBM PowerVM VIOS.

Does an attacker need local access to exploit this issue?

Yes. The issue is described as requiring a local attacker, who could gain elevated privileges through improper handling of symbolic links.

CVE-2026-16991: Vulnerabilities in IBM AIX and PowerVM VIOS

Affected Software

Remediation

Event History

Parent advisories

Frequently Asked Questions

Which IBM products are identified as affected?

Does an attacker need local access to exploit this issue?

Company

Resources

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