---
title: "CVE-2026-89448: Linux Kernel - Misconfiguration"
description: "Linux kernel contains a misconfiguration vulnerability in iommu/vt-d where ACS is not requested when tboot is enabled, causing potential security bypass due to disabled ACS, exploit requires tboot enabled."
url: https://panop.io/threat-heartbeat/CVE-2026-89448/
---

# CVE-2026-89448 Linux Kernel - Misconfiguration

Linux kernel contains a misconfiguration vulnerability in iommu/vt-d where ACS is not requested when tboot is enabled, causing potential security bypass due to disabled ACS, exploit requires tboot enabled.

CVSS base score 9.3 /10

Critical

CISA KEV

Not listed

Public exploit

None known

EPSS

0.14% chance of exploitation in 30 days

[View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-89448)

## Details

Type

Misconfiguration

Impact

Privilege Escalation

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Published

11 September 2026

Updated

15 October 2026

## Vendor fix

Update to the latest Linux kernel version with the ACS request fix in detect\_intel\_iommu.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

## References

- [https://nvd.nist.gov/vuln/detail/CVE-2026-89448](https://nvd.nist.gov/vuln/detail/CVE-2026-89448)
- [https://git.kernel.org/stable/c/607432b2618b61df81134be0ef2562b8300c1216](https://git.kernel.org/stable/c/607432b2618b61df81134be0ef2562b8300c1216)
- [https://git.kernel.org/stable/c/87bc611c6c98a41c00feb7b06b0c297dd141a2ae](https://git.kernel.org/stable/c/87bc611c6c98a41c00feb7b06b0c297dd141a2ae)
- [https://git.kernel.org/stable/c/aaeb81241e802c86be69394f72d49fde3f861fbb](https://git.kernel.org/stable/c/aaeb81241e802c86be69394f72d49fde3f861fbb)
- [https://git.kernel.org/stable/c/579eb867d3da63f3b5e32f235925e1daa7ec70d0](https://git.kernel.org/stable/c/579eb867d3da63f3b5e32f235925e1daa7ec70d0)
- [https://git.kernel.org/stable/c/45705a6bfdb283f7b3b509010fd617b72f942537](https://git.kernel.org/stable/c/45705a6bfdb283f7b3b509010fd617b72f942537)

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## What this record can't tell you

- Whether you run the affected software, and where
- Whether an attacker can actually reach and exploit it
- The misconfigurations that never get a CVE number
- What it would cost the business, ranked into what to fix first

Panop answers these inside your environment, for this CVE and every other finding.

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