CVE-2026-64244

Published Jul 24, 2026

Last updated 2 months ago

CVSS medium 5.5

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: drivers/base/memory: set mem->altmap after successful device registration If __add_memory_block() fails at xa_store() (under memory pressure for example), device_unregister() is called, which eventually triggers memory_block_release() with mem->altmap still set, causing a WARN_ON(mem->altmap). This was triggered by modifying virtio-mem driver. Fix this by delaying the assignment of mem->altmap until after __add_memory_block() has succeeded.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
NVD-CWE-noinfo

Social media

Hype score
Not currently trending

  1. 🚨*CVE* CVE-2026-64244 In the Linux kernel, the following vulnerability has been resolved: drivers/base/memory: set mem->altmap after successful device registration If __add_memory_block(… https://t.co/9TvPtLRqKg ----- Traducción: CVE-2026-64244 En … https://t.co/utm

    @infoflowcloud

    24 Jul 2026

    31 Impressions

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Configurations

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References

Sources include official advisories and independent security research.