# CVE-2024-36020: i40e: fix vf may be used uninitialized in this function warning

> A race condition in the i40e driver can cause servers to hang during resets due to uninitialized variable usage, leading to denial of service.

- **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:** 30 May 2024
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2024-36020, DEBIAN-CVE-2024-36020, UBUNTU-CVE-2024-36020

## What is CVE-2024-36020?

CVE-2024-36020 is a high-severity vulnerability in Debian Debian Linux, published on 30 May 2024. 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:

i40e: fix vf may be used uninitialized in this function warning

To fix the regression introduced by commit 52424f974bc5, which causes
servers hang in very hard to reproduce conditions with resets races.
Using two sources for the information is the root cause.
In this function before the fix bumping v didn't mean bumping vf
pointer. But the code used this variables interchangeably, so stale vf
could point to different/not intended vf.

Remove redundant "v" variable and iterate via single VF pointer across
whole function instead to guarantee VF pointer validity.

Weakness: CWE-908 (Use of Uninitialized Resource)

## Which versions are affected by CVE-2024-36020?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2024-36020?

Apply the vendor's patch.

## Is CVE-2024-36020 being exploited?

There is no known exploitation of CVE-2024-36020 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-36020 and fix it if it is affected.

What it is: CVE-2024-36020 is a high-severity vulnerability in Debian Debian Linux, published on 30 May 2024. 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-2024-36020 in the wild and no public exploit code.

Affected product: Debian Debian 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-2024-36020/ (Markdown: https://insights.sbomify.com/CVE-2024-36020/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-36020
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-36020
- OSV: https://osv.dev/vulnerability/CVE-2024-36020

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-36020/
Summaries are generated and may contain mistakes; the official description above is the record.