# CVE-2024-40996: bpf: Avoid splat in pskb_pull_reason

> A debug warning in the Linux kernel BPF subsystem can cause a kernel splat, potentially leading to a denial of service when specific debug configurations are enabled.

- **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:** 12 Jul 2024
- **Updated:** 23 May 2026
- **Also known as:** BELL-CVE-2024-40996, DEBIAN-CVE-2024-40996, GHSA-5x23-w3hg-qfcx, UBUNTU-CVE-2024-40996

## What is CVE-2024-40996?

CVE-2024-40996 is a high-severity denial of service vulnerability in Linux kernel, published on 12 Jul 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:

bpf: Avoid splat in pskb_pull_reason

syzkaller builds (CONFIG_DEBUG_NET=y) frequently trigger a debug
hint in pskb_may_pull.

We'd like to retain this debug check because it might hint at integer
overflows and other issues (kernel code should pull headers, not huge
value).

In bpf case, this splat isn't interesting at all: such (nonsensical)
bpf programs are typically generated by a fuzzer anyway.

Do what Eric suggested and suppress such warning.

For CONFIG_DEBUG_NET=n we don't need the extra check because
pskb_may_pull will do the right thing: return an error without the
WARN() backtrace.

## Which versions are affected by CVE-2024-40996?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-40996?

Apply the vendor's patch.

## Is CVE-2024-40996 being exploited?

There is no known exploitation of CVE-2024-40996 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-2024-40996 and fix it if it is affected.

What it is: CVE-2024-40996 is a high-severity denial of service vulnerability in Linux kernel, published on 12 Jul 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-2024-40996 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-2024-40996/ (Markdown: https://insights.sbomify.com/CVE-2024-40996/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-40996
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-40996
- OSV: https://osv.dev/vulnerability/CVE-2024-40996

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-40996/
Summaries are generated and may contain mistakes; the official description above is the record.