# CVE-2022-43972: Null pointer dereference in Linksys WRT54GL

> An unauthenticated attacker can cause a denial of service on Linksys WRT54GL routers by triggering a null pointer dereference in the UPnP service.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:A/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 9 Jan 2023
- **Updated:** 9 Apr 2025
- **Also known as:** GHSA-2p3f-3cj6-r8vv

## What is CVE-2022-43972?

CVE-2022-43972 is a medium-severity vulnerability in Linksys WRT54GL Wireless-G Broadband Router, published on 9 Jan 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A null pointer dereference vulnerability exists in Linksys WRT54GL Wireless-G Broadband Router with firmware <= 4.30.18.006. A null pointer dereference in the soap_action function within the upnp binary can be triggered by an unauthenticated attacker via a malicious POST request invoking the AddPortMapping action.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2022-43972?

It affects 1 product.


Products: Linksys Wrt54gl Firmware.

## How do I fix CVE-2022-43972?

No fix has been published for CVE-2022-43972 yet. Limit exposure of the affected software until one is available.

## Is CVE-2022-43972 being exploited?

There is no known exploitation of CVE-2022-43972 in the wild and no public exploit code.

## Other vulnerabilities in Linksys WRT54GL Wireless-G Broadband Router

- [CVE-2023-31742](https://insights.sbomify.com/CVE-2023-31742/): Command injection in n/a (high 7.2)
- [CVE-2022-43970](https://insights.sbomify.com/CVE-2022-43970/): Buffer overflow in Linksys WRT54GL (high 7.2)
- [CVE-2022-43973](https://insights.sbomify.com/CVE-2022-43973/): Arbitrary code execution in Linksys WRT54GL (high 7.2)
- [CVE-2024-1405](https://insights.sbomify.com/CVE-2024-1405/): Linksys WRT54GL Web Management Interface wlaninfo.htm information disclosure (medium 4.3)
- [CVE-2024-1406](https://insights.sbomify.com/CVE-2024-1406/): Linksys WRT54GL Web Management Interface SysInfo1.htm information disclosure (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-43972 and fix it if it is affected.

What it is: CVE-2022-43972 is a medium-severity vulnerability in Linksys WRT54GL Wireless-G Broadband Router, published on 9 Jan 2023. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-43972 in the wild and no public exploit code.

Affected product: Linksys WRT54GL Wireless-G Broadband Router. 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-2022-43972/ (Markdown: https://insights.sbomify.com/CVE-2022-43972/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-43972
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-43972
- OSV: https://osv.dev/vulnerability/CVE-2022-43972

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-43972/
Summaries are generated and may contain mistakes; the official description above is the record.