# CVE-2019-3819: Denial of service in kernel:

> A local privileged user can trigger an infinite loop in the Linux kernel HID debug driver, causing a system lockup and denial of service.

- **Severity:** Medium 4.2 (`CVSS:3.0/AV:L/AC:L/PR:H/UI:R/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 25 Jan 2019
- **Updated:** 4 Aug 2024
- **Also known as:** AZL-34853, AZL-6520, DEBIAN-CVE-2019-3819, GHSA-794c-rcrg-7j7w, UBUNTU-CVE-2019-3819

## What is CVE-2019-3819?

CVE-2019-3819 is a medium-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 25 Jan 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

A flaw was found in the Linux kernel in the function hid_debug_events_read() in drivers/hid/hid-debug.c file which may enter an infinite loop with certain parameters passed from a userspace. A local privileged user ("root") can cause a system lock up and a denial of service. Versions from v4.18 and newer are vulnerable.

Weakness: CWE-835 (Loop with Unreachable Exit Condition)

## Which versions are affected by CVE-2019-3819?

It affects 4 products.


Products: Canonical Ubuntu Linux, Debian Debian Linux, Linux kernel, Opensuse Leap.

## How do I fix CVE-2019-3819?

Apply the vendor's patch.

## Is CVE-2019-3819 being exploited?

There is no known exploitation of CVE-2019-3819 in the wild and no public exploit code.

## Other vulnerabilities in Canonical Ubuntu Linux

- [CVE-2020-11651](https://insights.sbomify.com/CVE-2020-11651/): SaltStack Salt Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2020-7247](https://insights.sbomify.com/CVE-2020-7247/): OpenSMTPD Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2019-16928](https://insights.sbomify.com/CVE-2019-16928/): Exim Out-of-bounds Write (critical 9.8, exploited in the wild)
- [CVE-2018-6789](https://insights.sbomify.com/CVE-2018-6789/): Exim Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2015-2590](https://insights.sbomify.com/CVE-2015-2590/): Oracle Java SE and Java SE Embedded Remote Code Execution (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-3819 and fix it if it is affected.

What it is: CVE-2019-3819 is a medium-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 25 Jan 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-2019-3819 in the wild and no public exploit code.

Affected product: Canonical Ubuntu 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-2019-3819/ (Markdown: https://insights.sbomify.com/CVE-2019-3819/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-3819
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-3819
- OSV: https://osv.dev/vulnerability/CVE-2019-3819

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-3819/
Summaries are generated and may contain mistakes; the official description above is the record.