# CVE-2026-90275: md/raid1: don't set array_frozen in raid1_takeover()

> A local attacker with high privileges can cause a permanent denial of service in Linux RAID1 arrays by triggering a takeover operation that leaves the array frozen.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-102684, BELL-CVE-2026-90275, DEBIAN-CVE-2026-90275, GHSA-c82r-j325-qwcg, UBUNTU-CVE-2026-90275

## What is CVE-2026-90275?

CVE-2026-90275 is a denial of service vulnerability in Linux, published on 17 Sep 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/raid1: don't set array_frozen in raid1_takeover()

raid1_takeover() sets conf->array_frozen = 1 on the newly-allocated
r1conf and nothing ever clears it, so every I/O to the array stalls
permanently once _wait_barrier() sees it stuck at 1.

This used to be harmless: level_store() called mddev_resume() right
after pers->run(), which called raid1_quiesce(mddev, 0) and cleared
array_frozen back to 0 regardless of what raid1_takeover() set. Commit
b39f35ebe86d ("md: don't quiesce in mddev_suspend()") removed that
quiesce(mddev, 0) call, so the pre-set now sticks.

setup_conf() already zero-initializes the new r1conf via kzalloc, so
just don't set array_frozen here.

Same class of bug as commit 892da88d1cd9 ("md/raid10: fix a
'conf->barrier' leakage in raid10_takeover()"), also triggered by
b39f35ebe86d.

## Which versions are affected by CVE-2026-90275?


## How do I fix CVE-2026-90275?

Apply the vendor's patch.

## Is CVE-2026-90275 being exploited?

There is no known exploitation of CVE-2026-90275 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90275 and fix it if it is affected.

What it is: CVE-2026-90275 is a denial of service vulnerability in Linux, published on 17 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-90275 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-90275/ (Markdown: https://insights.sbomify.com/CVE-2026-90275/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90275
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90275
- OSV: https://osv.dev/vulnerability/CVE-2026-90275

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90275/
Summaries are generated and may contain mistakes; the official description above is the record.