# CVE-2026-18822: IBM AIX and PowerVM VIOS denial of service via directory parsing

Source: https://junglewise.ai/threats/cve-2026-18822-ibm-aix-and-powervm-vios-denial-of-service-via-directory-parsing  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-20. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-18822 · Severity: medium · CVSS 4.4 · Published 2026-08-20

IBM AIX 7.2, 7.3 and PowerVM VIOS 4.1 contain a vulnerability in directory record parsing that allows a local attacker to consume excessive system resources, causing the operating system to become unresponsive. This could disrupt critical business operations on servers running these IBM operating systems.

Technologies: [IBM Aix](https://junglewise.ai/threats/technologies/aix), [IBM PowerVM VIOS](https://junglewise.ai/threats/technologies/powervm-vios). Vendors: [IBM](https://junglewise.ai/threats/vendors/ibm).

## Quick answers

**Is CVE-2026-18822 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-18822 being exploited in the wild.

**How severe is CVE-2026-18822?** Medium severity, with a CVSS score of 4.4, published 20 August 2026.

**Which products and versions are affected?** IBM Aix 7.2, 7.3; IBM PowerVM VIOS 4.1.

**Is there a fix for CVE-2026-18822?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-18822 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-18822?** Check whether you run IBM Aix or IBM PowerVM VIOS at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a resource consumption issue (CWE-400-class) in directory parsing logic within IBM AIX 7.2, 7.3 and PowerVM VIOS 4.1. A local attacker with system access can trigger uncontrolled resource consumption by crafting malicious directory records, leading to denial of service. The attack requires local access (not network-based) and no special privileges beyond basic user-level access. Successful exploitation results in system unavailability. IBM has released security updates via Service Packs and Fix Packs to remediate this issue.

## Affected products

- IBM AIX 7.2, 7.3
- IBM PowerVM VIOS 4.1

## Timeline

- 2026-08-20: disclosed

## References

- [https://www.ibm.com/support/pages/node/7283858](https://www.ibm.com/support/pages/node/7283858)

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