Description

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to achieve privilege escalation due to improper authorization.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.1",
  "pubDate": "2026-08-20T15:17:28.800Z",
  "pubdate": "2026-08-20T15:17:28.800Z",
  "executiveSummary": "This security analysis addresses a local privilege escalation vulnerability affecting IBM AIX and IBM PowerVM VIOS environments. The vulnerability stems from improper authorization controls within the affected operating system components, potentially allowing an authenticated local adversary to elevate their execution privileges beyond their intended security context.\nThe flaw impacts IBM AIX versions 7.2 and 7.3, alongside IBM PowerVM VIOS version 4.1. Successful exploitation of this authorization defect does not inherently require complex network exposure, as the attack vector is fundamentally local. However, an attacker must first establish a low-privileged execution context on the target operating system to interact with the vulnerable subsystem.\nThe risk implications are critical for multi-tenant or shared enterprise environments running the affected AIX and VIOS releases, as unauthorized privilege escalation can lead to complete host compromise, unauthorized access to sensitive system resources, and bypass of mandatory access controls or resource restrictions.\nRemediation requires applying the appropriate vendor-supplied patches or interim fixes designed to correct authorization validation logic within the affected OS components.",
  "technicalDetails": "The root cause of this vulnerability lies in improper authorization enforcement within specific administrative or system-level interfaces of IBM AIX 7.2, AIX 7.3, and IBM PowerVM VIOS 4.1. Specifically, the affected software fails to adequately validate whether a calling user possesses the requisite security clearances or administrative roles before granting access to privileged functional routines or operational contexts.\nThe exploitation method relies on a local attack vector where an authenticated user with minimal privileges interacts with the vulnerable component. Because authentication is required prior to exploitation, the threat actor must already possess valid local shell access or the ability to execute code within the local operating system environment. Network exposure is typically non-existent or secondary, as the vulnerability is driven by local systemic authorization flaws rather than remote listener exposure.\nThe step-by-step attack flow proceeds as follows: First, the low-privileged user identifies a vulnerable local mechanism, utility, or system call that improperly delegates or evaluates authorization credentials. Second, the attacker crafts a malicious input sequence, execution request, or environment manipulation designed to bypass the weak authorization checks implemented by the subsystem. Third, upon invoking the vulnerable function, the operating system kernel or privileged daemon processes the request without enforcing proper privilege verification boundaries.\nConsequently, the system grants the calling process elevated execution privileges, enabling the attacker to execute arbitrary administrative commands, manipulate protected system configurations, or access restricted data files reserved for root or highly privileged administrative roles.\nPost-exploitation impact includes full compromise of the local operating system instance or Virtual I/O Server (VIOS) partition. In virtualized environments utilizing PowerVM, compromising the VIOS layer can severely impact hypervisor-managed resources, virtual storage, and virtual networking across multiple client partitions, leading to cascading security failures across the enterprise infrastructure."
}