CVE-2026-45953 md/raid5: fix IO hang with degraded array with llbitmap

What is CVE-2026-45953?

CVE-2026-45953 is a medium-severity denial of service 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/raid5: fix IO hang with degraded array with llbitmap

When llbitmap bit state is still unwritten, any new write should force rcw, as bitmap_ops->blocks_synced() is checked in handle_stripe_dirtying(). However, later the same check is missing in need_this_block(), causing stripe to deadloop during handling because handle_stripe() will decide to go to handle_stripe_fill(), meanwhile need_this_block() always return 0 and nothing is handled.

Which versions are affected by CVE-2026-45953?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-45953?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-45953 being exploited?

There is no known exploitation of CVE-2026-45953 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-2026-45953, DEBIAN-CVE-2026-45953, GHSA-w54p-gjcx-42f6, UBUNTU-CVE-2026-45953.