# CVE-2025-40194: cpufreq: intel_pstate: Fix object lifecycle issue in update_qos_request()

> A use-after-free in the Linux kernel's intel_pstate driver can cause a system crash during CPU hot removal, requiring a kernel patch.

- **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:** 12 Nov 2025
- **Updated:** 11 May 2026
- **Also known as:** AZL-70094, BELL-CVE-2025-40194, DEBIAN-CVE-2025-40194, GHSA-8qw2-hj59-c25x, ROOT-OS-DEBIAN-11-CVE-2025-40194, ROOT-OS-DEBIAN-13-CVE-2025-40194, ROOT-OS-UBUNTU-2404-CVE-2025-40194, UBUNTU-CVE-2025-40194

## What is CVE-2025-40194?

CVE-2025-40194 is an use after free vulnerability in Linux, published on 12 Nov 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:

cpufreq: intel_pstate: Fix object lifecycle issue in update_qos_request()

The cpufreq_cpu_put() call in update_qos_request() takes place too early
because the latter subsequently calls freq_qos_update_request() that
indirectly accesses the policy object in question through the QoS request
object passed to it.

Fortunately, update_qos_request() is called under intel_pstate_driver_lock,
so this issue does not matter for changing the intel_pstate operation
mode, but it theoretically can cause a crash to occur on CPU device hot
removal (which currently can only happen in virt, but it is formally
supported nevertheless).

Address this issue by modifying update_qos_request() to drop the
reference to the policy later.

## Which versions are affected by CVE-2025-40194?


## How do I fix CVE-2025-40194?

Apply the vendor's patch.

## Is CVE-2025-40194 being exploited?

There is no known exploitation of CVE-2025-40194 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-40194 and fix it if it is affected.

What it is: CVE-2025-40194 is an use after free vulnerability in Linux, published on 12 Nov 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-2025-40194 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-2025-40194/ (Markdown: https://insights.sbomify.com/CVE-2025-40194/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-40194
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-40194
- OSV: https://osv.dev/vulnerability/CVE-2025-40194

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-40194/
Summaries are generated and may contain mistakes; the official description above is the record.