# CVE-2026-45861: gfs2: Fix slab-use-after-free in qd_put

> A use-after-free vulnerability in the Linux kernel's GFS2 filesystem allows attackers to cause denial of service or potentially execute code.

- **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:** 27 May 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-88524, BELL-CVE-2026-45861, DEBIAN-CVE-2026-45861, GHSA-v5c4-8mx9-g6x5, ROOT-OS-UBUNTU-2404-CVE-2026-45861, UBUNTU-CVE-2026-45861

## What is CVE-2026-45861?

CVE-2026-45861 is a high-severity use after free 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:

gfs2: Fix slab-use-after-free in qd_put

Commit a475c5dd16e5 ("gfs2: Free quota data objects synchronously")
started freeing quota data objects during filesystem shutdown instead of
putting them back onto the LRU list, but it failed to remove these
objects from the LRU list, causing LRU list corruption.  This caused
use-after-free when the shrinker (gfs2_qd_shrink_scan) tried to access
already-freed objects on the LRU list.

Fix this by removing qd objects from the LRU list before freeing them in
qd_put().

Initial fix from Deepanshu Kartikey <kartikey406@gmail.com>.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-45861?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-45861?

Apply the vendor's patch.

## Is CVE-2026-45861 being exploited?

There is no known exploitation of CVE-2026-45861 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-2026-45861 and fix it if it is affected.

What it is: CVE-2026-45861 is a high-severity use after free 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.
Exploitation: There is no known exploitation of CVE-2026-45861 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-2026-45861/ (Markdown: https://insights.sbomify.com/CVE-2026-45861/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-45861
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-45861
- OSV: https://osv.dev/vulnerability/CVE-2026-45861

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-45861/
Summaries are generated and may contain mistakes; the official description above is the record.