# CVE-2026-98091: btrfs: detach failed sprout device from transaction update list

> A use-after-free in the Linux kernel btrfs filesystem allows local attackers to cause a denial of service or potentially execute code by triggering a failed sprout device creation.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-104841, BELL-CVE-2026-98091, DEBIAN-CVE-2026-98091, GHSA-frx7-8j8j-mc25, UBUNTU-CVE-2026-98091

## What is CVE-2026-98091?

CVE-2026-98091 is a medium-severity use after free vulnerability in Linux kernel, published on 25 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:

btrfs: detach failed sprout device from transaction update list

When creating the first metadata chunk for a sprout filesystem,
create_chunk() adds the new device to the transaction dev_update_list
through device->post_commit_list.

If the subsequent system chunk creation fails, btrfs_init_new_device()
aborts the transaction and releases the device while post_commit_list is
still linked. This triggers a warning in btrfs_free_device() and leaves
the transaction list referencing freed memory.

Detach the device while holding chunk_mutex before releasing it.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-98091?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-98091?

Apply the vendor's patch.

## Is CVE-2026-98091 being exploited?

There is no known exploitation of CVE-2026-98091 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98091 and fix it if it is affected.

What it is: CVE-2026-98091 is a medium-severity use after free vulnerability in Linux kernel, published on 25 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-2026-98091 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-98091/ (Markdown: https://insights.sbomify.com/CVE-2026-98091/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98091
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98091
- OSV: https://osv.dev/vulnerability/CVE-2026-98091

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98091/
Summaries are generated and may contain mistakes; the official description above is the record.