Description
IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a remote attacker to cause a denial of service due to improper handling of a missing SSL client certificate.
Published: 2026-08-19
Score: 7.5 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

The vulnerability allows a remote attacker to cause a denial of service on IBM AIX 7.2, AIX 7.3, and IBM PowerVM VIOS 4.1 servers due to improper handling of a missing SSL client certificate. This is a CWE-400 resource exhaustion weakness, leading to a service disruption that compromises availability of the affected system.

Affected Systems

IBM AIX 7.2 and 7.3, and IBM PowerVM VIOS 4.1 are affected. The remediation levels are AIX 7.3 TL04 SP2, AIX 7.3 TL03 SP3, AIX 7.3 TL02 SP5, AIX 7.2 TL05 SP13, and VIOS 4.1.2 4.1.2.20, VIOS 4.1.1 4.1.1.30, and VIOS 4.1.0 4.1.0.50. These service packs and fix packs are cumulative, covering all previously published vulnerabilities.

Risk and Exploitability

The CVSS score of 7.5 classifies the vulnerability as high severity. EPSS is not available, so the likelihood of exploitation cannot be quantified, but the absence of a KEV listing suggests no known widespread attacks. The vulnerability requires remote reachability and the ability to initiate a connection that triggers the missing SSL client certificate handling, allowing an attacker to force the system to terminate services and achieve a denial of service.

Generated by OpenCVE AI on August 20, 2026 at 12:39 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

  • Download and install the applicable IBM AIX Service Pack or PowerVM VIOS Fix Pack from Fix Central.
  • Reboot the affected system, or use Live Update on AIX to complete the update.
  • For VIOS 4.1.0 or 4.1.1, migrate to Postgres15 by following the IBM post‑update instructions on the IBM support pages.
  • If using nimsh secure, follow IBM’s guidelines for the updated protocol steps during patch application.

Generated by OpenCVE AI on August 20, 2026 at 12:39 UTC.

Tracking

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Advisories

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History

Mon, 24 Aug 2026 16:00:00 +0000

Type Values Removed Values Added
First Time appeared Ibm vios
CPEs cpe:2.3:a:ibm:vios:*:*:*:*:*:*:*:*
cpe:2.3:o:ibm:aix:*:*:*:*:*:*:*:*
Vendors & Products Ibm vios

Wed, 19 Aug 2026 19:45:00 +0000

Type Values Removed Values Added
Description IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a remote attacker to cause a denial of service due to improper handling of a missing SSL client certificate.
Title Vulnerabilities in IBM AIX and PowerVM VIOS
First Time appeared Ibm
Ibm aix
Ibm powervm Vios
Weaknesses CWE-400
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': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Subscriptions

Ibm Aix Powervm Vios Vios
cve-icon MITRE

Status: PUBLISHED

Assigner: ibm

Published:

Updated: 2026-08-20T15:26:33.933Z

Reserved: 2026-07-24T02:53:47.456Z

Link: CVE-2026-16837

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2026-08-19T20:17:04.710

Modified: 2026-08-24T15:54:32.823

Link: CVE-2026-16837

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-20T12:45:03Z

Weaknesses
  • CWE-400

    Uncontrolled Resource Consumption