# CVE-2019-20917: Null dereference in n/a

> Remote attackers can crash the InspIRCd server via a NULL pointer dereference in the MySQL module when specific SQL modules are enabled.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/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:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 Sep 2020
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2019-20917, GHSA-8h73-696h-wwm7, UBUNTU-CVE-2019-20917

## What is CVE-2019-20917?

CVE-2019-20917 is a medium-severity vulnerability in Debian Debian Linux, published on 11 Sep 2020. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

An issue was discovered in InspIRCd 2 before 2.0.28 and 3 before 3.3.0. The mysql module contains a NULL pointer dereference when built against mariadb-connector-c 3.0.5 or newer. When combined with the sqlauth or sqloper modules, this vulnerability can be used for remote crashing of an InspIRCd server by any user able to connect to a server.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2019-20917?

It affects 2 products.


Products: Debian Debian Linux, Inspircd Inspircd.

## How do I fix CVE-2019-20917?

Upgrade to a fixed version.

## Is CVE-2019-20917 being exploited?

There is no known exploitation of CVE-2019-20917 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-20917 and fix it if it is affected.

What it is: CVE-2019-20917 is a medium-severity vulnerability in Debian Debian Linux, published on 11 Sep 2020. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2019-20917 in the wild and no public exploit code.

Affected product: Debian Debian 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-2019-20917/ (Markdown: https://insights.sbomify.com/CVE-2019-20917/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-20917
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-20917
- OSV: https://osv.dev/vulnerability/CVE-2019-20917

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-20917/
Summaries are generated and may contain mistakes; the official description above is the record.