CVE-2026-64244: drivers/base/memory: set mem->altmap after successful device registration

Q: What conditions are needed to trigger this issue?

The failure path is triggered when __add_memory_block() fails at xa_store(), such as under memory pressure. Cleanup then unregisters the device while mem->altmap is still set.

Published Jul 24, 2026

Updated

drivers/base/memory: set mem->altmap after successful device registration

Affected Software

7 affected componentsFixes available

Linux Kernel

Microsoft azl3 kernel 6.6.143.1-1<6.6.150.1-1

6.6.150.1-1

Linux Linux kernel>=6.6<6.6.144

Linux Linux kernel>=6.7<6.12.95

Linux Linux kernel>=6.13<6.18.37

Linux Linux kernel>=6.19<7.0.14

Linux Linux kernel>=7.1<7.1.2

Remediation

Event History

Jul 24, 2026

CVE Published

via MITRE·03:29 PM

Data Sourced

via MITRE·03:29 PM

Description

Data Sourced

via NVD·04:16 PM

RemedyDescriptionSeverityAffected Software

Jul 26, 2026

Data Sourced

via Microsoft·08:02 AM

DescriptionSeverityWeakness

Data Sourced

via Microsoft·08:02 AM

Affected Software

Updated

via Microsoft·08:02 AM

DescriptionSeverity

Frequently Asked Questions

What conditions are needed to trigger this issue?

The failure path is triggered when __add_memory_block() fails at xa_store(), such as under memory pressure. Cleanup then unregisters the device while mem->altmap is still set.

What access does an attacker need?

The supplied CVSS vector indicates local access and low privileges are required. No user interaction is required.

What is the expected security impact?

The rating indicates a high availability impact, with no confidentiality or integrity impact. The affected path can trigger WARN_ON(mem->altmap).

How can I mitigate the issue if it applies to my kernel?

A patch is available. No alternative workaround is provided in the available data.

How can I identify whether the failure has occurred?

Look for a WARN_ON(mem->altmap) warning associated with device cleanup after a failed memory-block registration. The described failure occurs when xa_store() fails during __add_memory_block().

CVE-2026-64244: drivers/base/memory: set mem->altmap after successful device registration

Affected Software

Remediation

Patch Available

Patch Available

Patch Available

Patch Available

Patch Available

Patch Available

Event History

Frequently Asked Questions

What conditions are needed to trigger this issue?

What access does an attacker need?

What is the expected security impact?

How can I mitigate the issue if it applies to my kernel?

How can I identify whether the failure has occurred?

Company

Resources

Contact

Frequently Asked Questions

What conditions are needed to trigger this issue?

What access does an attacker need?

What is the expected security impact?

How can I mitigate the issue if it applies to my kernel?

How can I identify whether the failure has occurred?