# CVE-2021-3970: Code injection in Notebook BIOS

> Local attackers with elevated privileges can execute arbitrary code via insufficient validation in Lenovo Notebook BIOS SMI handlers.

- **Severity:** Medium 6.7 (`CVSS:3.1/AV:L/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 22 Apr 2022
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-2g3v-5cpr-rx7q

## What is CVE-2021-3970?

CVE-2021-3970 is a medium-severity code injection vulnerability in Lenovo Notebook BIOS, published on 22 Apr 2022. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A potential vulnerability in LenovoVariable SMI Handler due to insufficient validation in some Lenovo Notebook models BIOS may allow an attacker with local access and elevated privileges to execute arbitrary code.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2021-3970?

It affects 105 products.


Products: Lenovo Ideapad 3-14ada05 Firmware, Lenovo Ideapad 3-14ada6 Firmware, Lenovo Ideapad 3-14alc6 Firmware, Lenovo Ideapad 3-14are05 Firmware, Lenovo Ideapad 3-14igl05 Firmware, Lenovo Ideapad 3-14iil05 Firmware, Lenovo Ideapad 3-14iml05 Firmware, Lenovo Ideapad 3-14itl05 Firmware, Lenovo Ideapad 3-14itl6 Firmware, Lenovo Ideapad 3-15ada05 Firmware, Lenovo Ideapad 3-15ada6 Firmware, Lenovo Ideapad 3-15alc6 Firmware, Lenovo Ideapad 3-15are05 Firmware, Lenovo Ideapad 3-15igl05 Firmware, Lenovo Ideapad 3-15iil05 Firmware, Lenovo Ideapad 3-15iml05 Firmware, Lenovo Ideapad 3-15itl05 Firmware, Lenovo Ideapad 3-15itl6 Firmware, Lenovo Ideapad 3-17ada05 Firmware, Lenovo Ideapad 3-17ada6 Firmware and 85 more.

## How do I fix CVE-2021-3970?

No fix has been published for CVE-2021-3970 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-3970 being exploited?

There is no known exploitation of CVE-2021-3970 in the wild and no public exploit code.

## Other vulnerabilities in Lenovo Notebook BIOS

- [CVE-2021-3971](https://insights.sbomify.com/CVE-2021-3971/): Privilege escalation in Notebook BIOS (medium 6.7)
- [CVE-2021-3972](https://insights.sbomify.com/CVE-2021-3972/): Security feature bypass in Notebook BIOS (medium 6.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-3970 and fix it if it is affected.

What it is: CVE-2021-3970 is a medium-severity code injection vulnerability in Lenovo Notebook BIOS, published on 22 Apr 2022. 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-2021-3970 in the wild and no public exploit code.

Affected product: Lenovo Notebook BIOS. 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-2021-3970/ (Markdown: https://insights.sbomify.com/CVE-2021-3970/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-3970
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-3970
- OSV: https://osv.dev/vulnerability/CVE-2021-3970

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-3970/
Summaries are generated and may contain mistakes; the official description above is the record.