# CVE-2021-29414: Security feature bypass in n/a

> Attackers with physical access can bypass security controls on STM32L4 microcontrollers, potentially compromising device integrity.

- **Severity:** Medium 6.1 (`CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:H/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:** 21 May 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-4qww-78q9-prqg

## What is CVE-2021-29414?

CVE-2021-29414 is a medium-severity vulnerability in n/a, published on 21 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

STMicroelectronics STM32L4 devices through 2021-03-29 have incorrect physical access control.

Weakness: CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component)

## Which versions are affected by CVE-2021-29414?

It affects 1 product.


Products: St Stm32cubel4 Firmware.

## How do I fix CVE-2021-29414?

No fix has been published for CVE-2021-29414 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-29414 being exploited?

There is no known exploitation of CVE-2021-29414 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2020-27212](https://insights.sbomify.com/CVE-2020-27212/): Security feature bypass in n/a (high 7.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-29414 and fix it if it is affected.

What it is: CVE-2021-29414 is a medium-severity vulnerability in n/a, published on 21 May 2021. 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-2021-29414 in the wild and no public exploit code.

Affected product: n/a. 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-2021-29414/ (Markdown: https://insights.sbomify.com/CVE-2021-29414/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-29414
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-29414
- OSV: https://osv.dev/vulnerability/CVE-2021-29414

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-29414/
Summaries are generated and may contain mistakes; the official description above is the record.