# CVE-2022-37797: Null dereference in n/a

> An attacker can crash the lighttpd web server by sending an invalid websocket handshake, causing a denial of service.

- **Severity:** High 7.5 (`CVSS:3.1/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:** 12 Sep 2022
- **Updated:** 3 Aug 2024
- **Also known as:** DEBIAN-CVE-2022-37797, DLA-3133-1, GHSA-cm5p-p299-9f4g, UBUNTU-CVE-2022-37797, openSUSE-SU-2022:10132-1, openSUSE-SU-2024:12327-1

## What is CVE-2022-37797?

CVE-2022-37797 is a high-severity vulnerability in Debian Debian Linux, published on 12 Sep 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In lighttpd 1.4.65, mod_wstunnel does not initialize a handler function pointer if an invalid HTTP request (websocket handshake) is received. It leads to null pointer dereference which crashes the server. It could be used by an external attacker to cause denial of service condition.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2022-37797?

It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `lighttpd` | SUSE:Package Hub 15 SP3 | All versions | 1.4.66-bp154.2.3.1 |
| `lighttpd` | SUSE:Package Hub 15 SP4 | All versions | 1.4.66-bp154.2.3.1 |
| `lighttpd` | openSUSE:Leap 15.3 | All versions | 1.4.66-bp154.2.3.1 |
| `lighttpd` | openSUSE:Leap 15.4 | All versions | 1.4.66-bp154.2.3.1 |
| `lighttpd` | openSUSE:Tumbleweed | All versions | 1.4.66-1.1 |

Products: Debian Debian Linux, Lighttpd Lighttpd.

## How do I fix CVE-2022-37797?

Apply the vendor's patch.

## Is CVE-2022-37797 being exploited?

There is no known exploitation of CVE-2022-37797 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-2022-37797 and fix it if it is affected.

What it is: CVE-2022-37797 is a high-severity vulnerability in Debian Debian Linux, published on 12 Sep 2022. 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-2022-37797 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-2022-37797/ (Markdown: https://insights.sbomify.com/CVE-2022-37797/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-37797
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-37797
- OSV: https://osv.dev/vulnerability/CVE-2022-37797

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-37797/
Summaries are generated and may contain mistakes; the official description above is the record.