Linux Kernel dm-integrity Superblock Validation Flaw

CVE-2026-99086

What is CVE-2026-99086?

The Linux Kernel's dm-integrity component has a vulnerability that occurs during the resume process of the device. The issue arises as the dm_integrity_resume() function fails to validate the superblock retrieved from the device, which may have been modified while the dm-integrity device was suspended. This lack of validation allows for potential misalignment between the in-memory structures and the actual state of the superblock, putting data integrity at risk. Specifically, the modification of the superblock by a malicious user can lead to improper handling of journal entries, resulting in unintended memory writes. To mitigate this risk, the superblock should be validated during construction, ensuring that changes to the on-disk geometry are detected and resume operations halted if inconsistencies are found.

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