# CVE-2022-48648: sfc: fix null pointer dereference in efx_hard_start_xmit

> A null pointer dereference in the sfc network driver can cause a kernel crash, leading to denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:** 28 Apr 2024
- **Updated:** 11 May 2026
- **Also known as:** DEBIAN-CVE-2022-48648, GHSA-559c-j26r-95qc, UBUNTU-CVE-2022-48648

## What is CVE-2022-48648?

CVE-2022-48648 is a medium-severity vulnerability in Linux kernel, published on 28 Apr 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:

sfc: fix null pointer dereference in efx_hard_start_xmit

Trying to get the channel from the tx_queue variable here is wrong
because we can only be here if tx_queue is NULL, so we shouldn't
dereference it. As the above comment in the code says, this is very
unlikely to happen, but it's wrong anyway so let's fix it.

I hit this issue because of a different bug that caused tx_queue to be
NULL. If that happens, this is the error message that we get here:
  BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
  [...]
  RIP: 0010:efx_hard_start_xmit+0x153/0x170 [sfc]

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2022-48648?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-48648?

Apply the vendor's patch.

## Is CVE-2022-48648 being exploited?

There is no known exploitation of CVE-2022-48648 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-2022-48648 and fix it if it is affected.

What it is: CVE-2022-48648 is a medium-severity vulnerability in Linux kernel, published on 28 Apr 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-2022-48648 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-2022-48648/ (Markdown: https://insights.sbomify.com/CVE-2022-48648/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-48648
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-48648
- OSV: https://osv.dev/vulnerability/CVE-2022-48648

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-48648/
Summaries are generated and may contain mistakes; the official description above is the record.