# CVE-2019-14850: Denial of service in nbdkit

> An attacker can cause resource exhaustion and service degradation in nbdkit by opening connections that trigger heavy backend plugin initialization.

- **Severity:** Low 3.7 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Mar 2021
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2019-14850, GHSA-j552-f62v-mc74, RHSA-2020:1167, UBUNTU-CVE-2019-14850

## What is CVE-2019-14850?

CVE-2019-14850 is a low-severity denial of service vulnerability in Redhat Enterprise Linux, published on 18 Mar 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A denial of service vulnerability was discovered in nbdkit 1.12.7, 1.14.1 and 1.15.1. An attacker could connect to the nbdkit service and cause it to perform a large amount of work in initializing backend plugins, by simply opening a connection to the service. This vulnerability could cause resource consumption and degradation of service in nbdkit, depending on the plugins configured on the server-side.

Weakness: CWE-406 (Insufficient Control of Network Message Volume (Network Amplification))

## Which versions are affected by CVE-2019-14850?

It affects 4 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `nbdkit` | Red Hat:enterprise_linux:7::server | All versions | 0:1.8.0-3.el7 |
| `nbdkit-basic-plugins` | Red Hat:enterprise_linux:7::server | All versions | 0:1.8.0-3.el7 |
| `nbdkit-debuginfo` | Red Hat:enterprise_linux:7::server | All versions | 0:1.8.0-3.el7 |
| `nbdkit-devel` | Red Hat:enterprise_linux:7::server | All versions | 0:1.8.0-3.el7 |
| `nbdkit-example-plugins` | Red Hat:enterprise_linux:7::server | All versions | 0:1.8.0-3.el7 |
| `nbdkit-plugin-python-common` | Red Hat:enterprise_linux:7::server | All versions | 0:1.8.0-3.el7 |
| `nbdkit-plugin-python2` | Red Hat:enterprise_linux:7::server | All versions | 0:1.8.0-3.el7 |
| `nbdkit-plugin-vddk` | Red Hat:enterprise_linux:7::server | All versions | 0:1.8.0-3.el7 |

Products: Nbdkit Project Nbdkit, Redhat Enterprise Linux, Redhat Enterprise Linux Server, Redhat Virtualization.

## How do I fix CVE-2019-14850?

Apply the vendor's patch.

## Is CVE-2019-14850 being exploited?

There is no known exploitation of CVE-2019-14850 in the wild and no public exploit code.

## Other vulnerabilities in Redhat Enterprise Linux

- [CVE-2025-47711](https://insights.sbomify.com/CVE-2025-47711/): Nbdkit: nbdkit-server: off-by-one error when processing block status may lead to a denial of service (medium 6.5)
- [CVE-2025-47712](https://insights.sbomify.com/CVE-2025-47712/): Nbd: nbdkit: integer overflow triggers an assertion resulting in denial of service (medium 6.5)
- [CVE-2019-14851](https://insights.sbomify.com/CVE-2019-14851/): Denial of service in nbdkit (medium 6.5)
- [CVE-2021-3716](https://insights.sbomify.com/CVE-2021-3716/): Other in nbdkit (low 3.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-14850 and fix it if it is affected.

What it is: CVE-2019-14850 is a low-severity denial of service vulnerability in Redhat Enterprise Linux, published on 18 Mar 2021. 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-2019-14850 in the wild and no public exploit code.

Affected product: Redhat Enterprise Linux. 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-2019-14850/ (Markdown: https://insights.sbomify.com/CVE-2019-14850/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-14850
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-14850
- OSV: https://osv.dev/vulnerability/CVE-2019-14850

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-14850/
Summaries are generated and may contain mistakes; the official description above is the record.