ibm aix CVE-2026-16838 vulnerability in IBM Products
Published on August 19, 2026

Vulnerabilities in IBM AIX and PowerVM VIOS
IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to overwrite critical files and obtain sensitive information due to a time-of-check to time-of-use (TOCTOU) race condition.

Vendor Advisory NVD

Vulnerability Analysis

CVE-2026-16838 is exploitable with local system access, and requires small amount of user privileges. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.

Attack Vector:
LOCAL
Attack Complexity:
HIGH
Privileges Required:
LOW
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
HIGH
Integrity Impact:
HIGH
Availability Impact:
HIGH

Weakness Type

What is a TOCTTOU Vulnerability?

The software checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the software to perform invalid actions when the resource is in an unexpected state. This weakness can be security-relevant when an attacker can influence the state of the resource between check and use. This can happen with shared resources such as files, memory, or even variables in multithreaded programs.

CVE-2026-16838 has been classified to as a TOCTTOU vulnerability or weakness.


Products Associated with CVE-2026-16838

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Affected Versions

IBM AIX: IBM PowerVM VIOS: