# CVE-2019-19815: Null dereference in n/a

> A crafted f2fs filesystem image can cause a NULL pointer dereference in the Linux kernel, leading to a denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 17 Dec 2019
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2019-19815, GHSA-8x8c-w6cj-qp86, UBUNTU-CVE-2019-19815

## What is CVE-2019-19815?

CVE-2019-19815 is a medium-severity vulnerability in Linux kernel, published on 17 Dec 2019. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

In the Linux kernel 5.0.21, mounting a crafted f2fs filesystem image can cause a NULL pointer dereference in f2fs_recover_fsync_data in fs/f2fs/recovery.c. This is related to F2FS_P_SB in fs/f2fs/f2fs.h.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2019-19815?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2019-19815?

Apply the vendor's patch.

## Is CVE-2019-19815 being exploited?

There is no known exploitation of CVE-2019-19815 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-2019-19815 and fix it if it is affected.

What it is: CVE-2019-19815 is a medium-severity vulnerability in Linux kernel, published on 17 Dec 2019. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2019-19815 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-2019-19815/ (Markdown: https://insights.sbomify.com/CVE-2019-19815/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-19815
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-19815
- OSV: https://osv.dev/vulnerability/CVE-2019-19815

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-19815/
Summaries are generated and may contain mistakes; the official description above is the record.