# CVE-2022-40740: Realtek GPON router - Command Injection

> An authenticated administrator can execute arbitrary system commands on Realtek GPON routers due to insufficient input filtering.

- **Severity:** High 7.2 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 3 Jan 2023
- **Updated:** 10 Apr 2025
- **Also known as:** GHSA-h56c-fjpj-2m9w

## What is CVE-2022-40740?

CVE-2022-40740 is a high-severity command injection vulnerability in Realtek GPON router, published on 3 Jan 2023. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

Realtek GPON router has insufficient filtering for special characters. A remote attacker authenticated as an administrator can exploit this vulnerability to perform command injection attacks, to execute arbitrary system command, manipulate system or disrupt service.

Weakness: CWE-78 (Improper Neutralization of Special Elements used in an OS Command)

## Which versions are affected by CVE-2022-40740?

It affects 2 products.


Products: Realtek Usdk, Realtek Xpon Software Development Kit.

## How do I fix CVE-2022-40740?

No fix has been published for CVE-2022-40740 yet. Limit exposure of the affected software until one is available.

## Is CVE-2022-40740 being exploited?

There is no known exploitation of CVE-2022-40740 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-40740 and fix it if it is affected.

What it is: CVE-2022-40740 is a high-severity command injection vulnerability in Realtek GPON router, published on 3 Jan 2023. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-40740 in the wild and no public exploit code.

Affected product: Realtek GPON 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-2022-40740/ (Markdown: https://insights.sbomify.com/CVE-2022-40740/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-40740
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-40740
- OSV: https://osv.dev/vulnerability/CVE-2022-40740

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-40740/
Summaries are generated and may contain mistakes; the official description above is the record.