# CVE-2019-20054: Null dereference in n/a

> A NULL pointer dereference in the Linux kernel allows local attackers to cause a system crash via the proc filesystem.

- **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 Dec 2019
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2019-20054, GHSA-jgf2-2xcw-5gxx, UBUNTU-CVE-2019-20054

## What is CVE-2019-20054?

CVE-2019-20054 is a medium-severity vulnerability in Linux kernel, published on 28 Dec 2019. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel before 5.0.6, there is a NULL pointer dereference in drop_sysctl_table() in fs/proc/proc_sysctl.c, related to put_links, aka CID-23da9588037e.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2019-20054?

It affects 13 products.


Products: Linux kernel, Netapp 8300 Firmware, Netapp 8700 Firmware, Netapp A400 Firmware, Netapp Active Iq Unified Manager, Netapp Cloud Backup, Netapp Data Availability Services, Netapp E-Series Santricity Os Controller, Netapp Fas\/Aff Baseboard Management Controller, Netapp H610s Firmware, Netapp Solidfire \& Hci Management Node, Netapp Solidfire Baseboard Management Controller, Netapp Steelstore Cloud Integrated Storage.

## How do I fix CVE-2019-20054?

Apply the vendor's patch.

## Is CVE-2019-20054 being exploited?

There is no known exploitation of CVE-2019-20054 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-2019-20054 and fix it if it is affected.

What it is: CVE-2019-20054 is a medium-severity vulnerability in Linux kernel, published on 28 Dec 2019. 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-2019-20054 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-2019-20054/ (Markdown: https://insights.sbomify.com/CVE-2019-20054/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-20054
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-20054
- OSV: https://osv.dev/vulnerability/CVE-2019-20054

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-20054/
Summaries are generated and may contain mistakes; the official description above is the record.