CVE-2026-46045 md/md-llbitmap: skip reading rdevs that are not in_sync

What is CVE-2026-46045?

CVE-2026-46045 is a high-severity vulnerability in Linux kernel, published on 27 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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

md/md-llbitmap: skip reading rdevs that are not in_sync

When reading bitmap pages from member disks, the code iterates through all rdevs and attempts to read from the first available one. However, it only checks for raid_disk assignment and Faulty flag, missing the In_sync flag check.

This can cause bitmap data to be read from spare disks that are still being rebuilt and don't have valid bitmap information yet. Reading stale or uninitialized bitmap data from such disks can lead to incorrect dirty bit tracking, potentially causing data corruption during recovery or normal operation.

Add the In_sync flag check to ensure bitmap pages are only read from fully synchronized member disks that have valid bitmap data.

Weakness: CWE-787

Which versions are affected by CVE-2026-46045?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-46045?

Apply the vendor's patch.

Is CVE-2026-46045 being exploited?

There is no known exploitation of CVE-2026-46045 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-46045, DEBIAN-CVE-2026-46045, GHSA-5mq8-r2rm-q3gq, UBUNTU-CVE-2026-46045.