# CVE-2023-54081: xen: speed up grant-table reclaim

> A flaw in the Linux kernel's Xen grant-table reclaim mechanism can cause memory leaks and VM freezes, impacting Qubes OS users.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Dec 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2023-54081, DEBIAN-CVE-2023-54081, GHSA-x4pm-f62g-mp4x, ROOT-OS-DEBIAN-11-CVE-2023-54081, ROOT-OS-UBUNTU-2204-CVE-2023-54081, UBUNTU-CVE-2023-54081

## What is CVE-2023-54081?

CVE-2023-54081 is a denial of service vulnerability in Linux, published on 24 Dec 2025. 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:

xen: speed up grant-table reclaim

When a grant entry is still in use by the remote domain, Linux must put
it on a deferred list.  Normally, this list is very short, because
the PV network and block protocols expect the backend to unmap the grant
first.  However, Qubes OS's GUI protocol is subject to the constraints
of the X Window System, and as such winds up with the frontend unmapping
the window first.  As a result, the list can grow very large, resulting
in a massive memory leak and eventual VM freeze.

To partially solve this problem, make the number of entries that the VM
will attempt to free at each iteration tunable.  The default is still
10, but it can be overridden via a module parameter.

This is Cc: stable because (when combined with appropriate userspace
changes) it fixes a severe performance and stability problem for Qubes
OS users.

## Which versions are affected by CVE-2023-54081?


## How do I fix CVE-2023-54081?

Apply the vendor's patch.

## Is CVE-2023-54081 being exploited?

There is no known exploitation of CVE-2023-54081 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-54081 and fix it if it is affected.

What it is: CVE-2023-54081 is a denial of service vulnerability in Linux, published on 24 Dec 2025. 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-2023-54081 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-2023-54081/ (Markdown: https://insights.sbomify.com/CVE-2023-54081/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-54081
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-54081
- OSV: https://osv.dev/vulnerability/CVE-2023-54081

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-54081/
Summaries are generated and may contain mistakes; the official description above is the record.