# CVE-2021-41842: Missing authorization in n/a

> Attackers can execute arbitrary code in the SMM environment due to a missing CommBuffer check in the AtaLegacySmm handler.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 5 Jan 2022
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-v6qx-c5rh-4q6q

## What is CVE-2021-41842?

CVE-2021-41842 is a critical missing authorization vulnerability in Insyde Insydeh2o, published on 5 Jan 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An issue was discovered in AtaLegacySmm in the kernel 5.0 before 05.08.46, 5.1 before 05.16.46, 5.2 before 05.26.46, 5.3 before 05.35.46, 5.4 before 05.43.46, and 5.5 before 05.51.45 in Insyde InsydeH2O. Code execution can occur because the SMI handler lacks a CommBuffer check.

## Which versions are affected by CVE-2021-41842?

It affects 1 product.


Products: Insyde Insydeh2o.

## How do I fix CVE-2021-41842?

No fix has been published for CVE-2021-41842 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-41842 being exploited?

There is no known exploitation of CVE-2021-41842 in the wild and no public exploit code.

## Other vulnerabilities in Insyde Insydeh2o

- [CVE-2023-22612](https://insights.sbomify.com/CVE-2023-22612/): Memory corruption in n/a (high 8.8)
- [CVE-2023-22613](https://insights.sbomify.com/CVE-2023-22613/): Memory corruption in n/a (high 8.8)
- [CVE-2023-22614](https://insights.sbomify.com/CVE-2023-22614/): Memory corruption in n/a (high 8.8)
- [CVE-2023-22615](https://insights.sbomify.com/CVE-2023-22615/): Memory corruption in n/a (high 8.4)
- [CVE-2022-36448](https://insights.sbomify.com/CVE-2022-36448/): Memory corruption in n/a (high 8.2)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-41842 and fix it if it is affected.

What it is: CVE-2021-41842 is a critical missing authorization vulnerability in Insyde Insydeh2o, published on 5 Jan 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-2021-41842 in the wild and no public exploit code.

Affected product: Insyde Insydeh2o. 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-2021-41842/ (Markdown: https://insights.sbomify.com/CVE-2021-41842/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-41842
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-41842
- OSV: https://osv.dev/vulnerability/CVE-2021-41842

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-41842/
Summaries are generated and may contain mistakes; the official description above is the record.