# CVE-2026-90216: ubi: Fix rollback for explicit UBI device numbers

> A logic error in Linux kernel UBI initialization rollback can cause resource leaks or instability when explicit device numbers are used, requiring local privileged access.

- **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-102449, BELL-CVE-2026-90216, DEBIAN-CVE-2026-90216, GHSA-98x6-774g-8659, UBUNTU-CVE-2026-90216

## What is CVE-2026-90216?

CVE-2026-90216 is a 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:

ubi: Fix rollback for explicit UBI device numbers

ubi_init_attach() rolls back module initialization failures by scanning
ubi_devices[0..i-1], where i is the mtd= parameter index. That assumes
the parameter index matches the UBI device number.

That assumption is not true when mtd= specifies an explicit ubi_num. A
successfully attached device can be stored at a higher ubi_devices[]
slot, and a later failure can miss it during rollback.

Scan the full ubi_devices[] array and detach by the actual array index,
matching the way UBI devices are stored.

## Which versions are affected by CVE-2026-90216?


## How do I fix CVE-2026-90216?

Apply the vendor's patch.

## Is CVE-2026-90216 being exploited?

There is no known exploitation of CVE-2026-90216 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90216 and fix it if it is affected.

What it is: CVE-2026-90216 is a 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-2026-90216 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-2026-90216/ (Markdown: https://insights.sbomify.com/CVE-2026-90216/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90216
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90216
- OSV: https://osv.dev/vulnerability/CVE-2026-90216

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90216/
Summaries are generated and may contain mistakes; the official description above is the record.