CVE-2026-16927 Vulnerabilities in IBM AIX and PowerVM VIOS

High 7.3 Published 20 Aug 2026 Updated 21 Aug 2026

A local attacker can exploit a TOCTOU race condition in IBM AIX and PowerVM VIOS to gain root privileges.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: A user has to click or open something
Fix: None listed

What is CVE-2026-16927?

CVE-2026-16927 is a high-severity vulnerability in Ibm Aix, published on 20 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to gain root privileges due to a time-of-check to time-of-use (TOCTOU) race condition.

Weakness: CWE-367

Which versions are affected by CVE-2026-16927?

It affects 2 products.

Products include Ibm Aix, Ibm Vios.

How do I fix CVE-2026-16927?

No fix has been published for CVE-2026-16927 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-16927 being exploited?

There is no known exploitation of CVE-2026-16927 in the wild and no public exploit code.

All Ibm Aix vulnerabilities

Sources

Also known as GHSA-4h65-qr29-cvw4.