CVE-2026-43484: mmc: core: Avoid bitfield RMW for claim/retune flags

Published May 13, 2026
·
Updated

In the Linux kernel, the following vulnerability has been resolved:

mmc: core: Avoid bitfield RMW for claim/retune flags

Move claimed and retune control flags out of the bitfield word to avoid unrelated RMW side effects in asynchronous contexts.

The host->claimed bit shared a word with retune flags. Writes to claimed in mmcclaimhost() or retunenow in mmcmqqueuerq() can overwrite other bits when concurrent updates happen in other contexts, triggering spurious WARNON(!host->claimed). Convert claimed, canretune, retunenow and retunepaused to bool to remove shared-word coupling.

Affected Software

8 affected components
Linux Linux kernel
Linux Linux kernel>=4.15<5.15.203
Linux Linux kernel>=5.16<6.1.167
Linux Linux kernel>=6.2<6.6.130
Linux Linux kernel>=6.7<6.12.78
Linux Linux kernel>=6.13<6.18.19
Linux Linux kernel>=6.19<6.19.9
Linux Linux kernel=7.0-rc1

Event History

May 13, 2026
CVE Published
via MITRE·03:08 PM
Data Sourced
via MITRE·03:08 PM
Description
Data Sourced
via NVD·04:16 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2026-43484?

CVE-2026-43484 has been classified as a medium severity vulnerability due to potential impacts on security and stability.

2

How do I fix CVE-2026-43484?

To resolve CVE-2026-43484, update to the latest version of the Linux kernel that includes the patch for this vulnerability.

3

What systems are affected by CVE-2026-43484?

CVE-2026-43484 affects the Linux kernel across various distributions.

4

What type of vulnerability is CVE-2026-43484?

CVE-2026-43484 is a race condition vulnerability related to bitfield read-modify-write operations.

5

Can CVE-2026-43484 be exploited remotely?

Yes, CVE-2026-43484 can potentially be exploited remotely under certain conditions.

Contact

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