# CVE-2026-31455: xfs: stop reclaim before pushing AIL during unmount

> A race condition in the Linux kernel XFS filesystem during unmount can lead to use-after-free, potentially allowing code execution or system crashes.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 22 Apr 2026
- **Updated:** 11 May 2026
- **Also known as:** AZL-83207, BELL-CVE-2026-31455, DEBIAN-CVE-2026-31455, GHSA-q892-7mjj-mjx9, ROOT-OS-DEBIAN-11-CVE-2026-31455, ROOT-OS-DEBIAN-12-CVE-2026-31455, ROOT-OS-DEBIAN-13-CVE-2026-31455, ROOT-OS-UBUNTU-2204-CVE-2026-31455, ROOT-OS-UBUNTU-2404-CVE-2026-31455, UBUNTU-CVE-2026-31455

## What is CVE-2026-31455?

CVE-2026-31455 is a high-severity use after free vulnerability in Linux kernel, published on 22 Apr 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:

xfs: stop reclaim before pushing AIL during unmount

The unmount sequence in xfs_unmount_flush_inodes() pushed the AIL while
background reclaim and inodegc are still running. This is broken
independently of any use-after-free issues - background reclaim and
inodegc should not be running while the AIL is being pushed during
unmount, as inodegc can dirty and insert inodes into the AIL during the
flush, and background reclaim can race to abort and free dirty inodes.

Reorder xfs_unmount_flush_inodes() to stop inodegc and cancel background
reclaim before pushing the AIL. Stop inodegc before cancelling
m_reclaim_work because the inodegc worker can re-queue m_reclaim_work
via xfs_inodegc_set_reclaimable.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-31455?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-31455?

Apply the vendor's patch.

## Is CVE-2026-31455 being exploited?

There is no known exploitation of CVE-2026-31455 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-2026-31455 and fix it if it is affected.

What it is: CVE-2026-31455 is a high-severity use after free vulnerability in Linux kernel, published on 22 Apr 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-2026-31455 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-2026-31455/ (Markdown: https://insights.sbomify.com/CVE-2026-31455/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-31455
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-31455
- OSV: https://osv.dev/vulnerability/CVE-2026-31455

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-31455/
Summaries are generated and may contain mistakes; the official description above is the record.