# CVE-2018-16871: Null dereference in kernel:

> An attacker can crash the NFS server by triggering a null pointer dereference via an invalid sequence, causing denial of service and data loss.

- **Severity:** High 7.5 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 30 Jul 2019
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2018-16871, GHSA-h4fx-7429-jvf7, UBUNTU-CVE-2018-16871

## What is CVE-2018-16871?

CVE-2018-16871 is a high-severity vulnerability in Linux kernel, published on 30 Jul 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A flaw was found in the Linux kernel's NFS implementation, all versions 3.x and all versions 4.x up to 4.20. An attacker, who is able to mount an exported NFS filesystem, is able to trigger a null pointer dereference by using an invalid NFS sequence. This can panic the machine and deny access to the NFS server. Any outstanding disk writes to the NFS server will be lost.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2018-16871?

It affects 20 products.


Products: Linux kernel, Netapp Cloud Backup, Netapp H300e Firmware, Netapp H300s Firmware, Netapp H410c Firmware, Netapp H410s Firmware, Netapp H500e Firmware, Netapp H500s Firmware, Netapp H700e Firmware, Netapp H700s Firmware, Redhat Developer Tools, Redhat Enterprise Linux, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Eus, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Eus, Redhat Enterprise Linux Server Tus, Redhat Enterprise Linux Workstation, Redhat Mrg Realtime.

## How do I fix CVE-2018-16871?

Apply the vendor's patch.

## Is CVE-2018-16871 being exploited?

There is no known exploitation of CVE-2018-16871 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-2018-16871 and fix it if it is affected.

What it is: CVE-2018-16871 is a high-severity vulnerability in Linux kernel, published on 30 Jul 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2018-16871 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-2018-16871/ (Markdown: https://insights.sbomify.com/CVE-2018-16871/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-16871
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-16871
- OSV: https://osv.dev/vulnerability/CVE-2018-16871

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-16871/
Summaries are generated and may contain mistakes; the official description above is the record.