Description
IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to execute arbitrary code due to a time-of-check to time-of-use (TOCTOU) race condition.
Published: 2026-08-20
Score: 7 High
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

This vulnerability arises from a time‑of‑check to time‑of‑use race condition (CWE‑367) in IBM AIX 7.2, AIX 7.3, and PowerVM VIOS 4.1. A local attacker can exploit the race to execute arbitrary code on the affected systems.

Affected Systems

Affected systems include IBM AIX 7.2 and 7.3 releases and IBM PowerVM VIOS 4.1. The advised remediation levels are IBM AIX Service Packs such as AIX 7.3 TL04 SP2, AIX 7.3 TL03 SP3, AIX 7.3 TL02 SP5, AIX 7.2 TL05 SP13, and IBM PowerVM VIOS Fix Packs 4.1.0.50, 4.1.1.30, and 4.1.2.20, which are cumulative and cover all previously published issues.

Risk and Exploitability

The CVSS score of 7 indicates a medium‑to‑high risk and the vulnerability can be exploited only by a local attacker, as the attack vector is local. The EPSS score is not disclosed, and the vulnerability is not listed in CISA’s KEV catalog, but the presence of a local arbitrary‑code path warrants immediate patching. An LPAR reboot is required to complete the update, though Live Update can avoid rebooting on AIX.

Generated by OpenCVE AI on August 20, 2026 at 19:57 UTC.

Remediation

Vendor Solution

A.  APARS IBM has assigned the following APARs to this problem: AIX LevelAPARAvailability  SPKEY7.2.5IJ5956608/14/2026SP13key_w_apar7.3.2IJ5956508/14/2026SP05key_w_apar7.3.3IJ5956408/14/2026SP03key_w_apar7.3.4IJ59563 08/14/2026SP02key_w_apar VIOS LevelAPARAvailability SPKEY4.1.0IJ5956508/14/20264.1.0.50key_w_apar4.1.1IJ5956408/14/20264.1.1.30key_w_apar4.1.2IJ5956308/14/20264.1.2.20key_w_apar B.  FIXES IBM strongly recommends addressing the vulnerability now.  AIX and VIOS fixes are available and can be downloaded from Fix Central: https://www.ibm.com/support/fixcentral  An LPAR reboot is required to complete the SP/FP update. On AIX, Live Update can be used to avoid a reboot.  IBM has assigned the following AIX Service Packs (SPs) and VIOS Fix Packs (FPs) as the remediation levels for the published vulnerabilities. AIX Level Service PackAIX 7.3 TL04SP2AIX 7.3 TL03SP3AIX 7.3 TL02SP5AIX 7.2 TL05 SP13 PowerVM VIOS LevelFix PackVIOS 4.1.2 4.1.2.20VIOS 4.1.1 4.1.1.30VIOS 4.1.0  4.1.0.50 Note: These SPs/FPs are cumulative and include fixes for all previously published AIX/VIOS security vulnerabilities. They can be applied on top of any earlier affected level of the TL . Note: To apply these patches using nimsh secure, special steps must be taken as the protocol between master and client is updated to be more secure. Please read this article: https://www.ibm.com/support/pages/node/7283157 Note: For VIOS 4.1.0 and VIOS 4.1.1, additional steps are required to migrate to the latest Postgres15 after applying the 4.1.1.30 or 4.1.0.50 FPs above. Instructions to do that can be found here:                             4.1.0.50 post-update instructions: https://www.ibm.com/support/pages/node/7283819           4.1.1.30 post-update instructions: https://www.ibm.com/support/pages/node/7283823

OpenCVE Recommended Actions

  • Apply the latest IBM AIX Service Pack for the affected AIX release (e.g., SP2 for AIX 7.3 or SP13 for AIX 7.2) from Fix Central.
  • Install the corresponding PowerVM VIOS Fix Pack (4.1.0.50 for VIOS 4.1.0, 4.1.1.30 for VIOS 4.1.1, or 4.1.2.20 for VIOS 4.1.2) from Fix Central.
  • Perform the LPAR reboot required to complete the SP/FP update, or use AIX Live Update to avoid reboot if available.
  • When using nimsh secure, follow IBM’s special steps to maintain secure protocol during the update.
  • After applying VIOS 4.1.0 or 4.1.1 security fixes, migrate to Postgres 15 using IBM’s post‑update instructions linked from IBM support.

Generated by OpenCVE AI on August 20, 2026 at 19:57 UTC.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Thu, 20 Aug 2026 17:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Thu, 20 Aug 2026 14:45:00 +0000

Type Values Removed Values Added
Description IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to execute arbitrary code due to a time-of-check to time-of-use (TOCTOU) race condition.
Title Vulnerabilities in IBM AIX and PowerVM VIOS
First Time appeared Ibm
Ibm aix
Ibm powervm Vios
Weaknesses CWE-367
CPEs cpe:2.3:a:ibm:aix:7.2.0:*:*:*:*:*:*:*
cpe:2.3:a:ibm:aix:7.2:*:*:*:*:*:*:*
cpe:2.3:a:ibm:aix:7.3.0:*:*:*:*:*:*:*
cpe:2.3:a:ibm:aix:7.3:*:*:*:*:*:*:*
cpe:2.3:a:ibm:powervm_vios:4.1.0:*:*:*:*:*:*:*
cpe:2.3:a:ibm:powervm_vios:4.1:*:*:*:*:*:*:*
Vendors & Products Ibm
Ibm aix
Ibm powervm Vios
References
Metrics cvssV3_1

{'score': 7, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

Subscriptions

Ibm Aix Powervm Vios
cve-icon MITRE

Status: PUBLISHED

Assigner: ibm

Published:

Updated: 2026-08-21T03:55:51.283Z

Reserved: 2026-07-24T07:05:03.530Z

Link: CVE-2026-16922

cve-icon Vulnrichment

Updated: 2026-08-20T16:18:47.936Z

cve-icon NVD

Status : Received

Published: 2026-08-20T15:17:28.263

Modified: 2026-08-21T04:17:52.193

Link: CVE-2026-16922

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-20T20:00:05Z

Weaknesses
  • CWE-367

    Time-of-check Time-of-use (TOCTOU) Race Condition