# CVE-2023-4020: Unvalidated input in Silicon Labs PSA Attestation service leads to secure memory access from non-secure memory

> Attackers can read or write secure memory from non-secure regions due to unvalidated input in the PSA Attestation service.

- **Severity:** Critical 9.0 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N`)
- **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:** 15 Dec 2023
- **Updated:** 26 Sep 2024
- **Also known as:** GHSA-2cr6-32m2-cxhc

## What is CVE-2023-4020?

CVE-2023-4020 is a critical memory corruption vulnerability in silabs.com GSDK, published on 15 Dec 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An unvalidated input in a library function responsible for communicating between secure and non-secure memory in Silicon Labs TrustZone implementation allows reading/writing of memory in the secure region of memory from the non-secure region of memory.

Weakness: CWE-787 (Out-of-bounds Write), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2023-4020?

It affects 1 product.


Products: Silabs Gecko Software Development Kit.

## How do I fix CVE-2023-4020?

No fix has been published for CVE-2023-4020 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-4020 being exploited?

There is no known exploitation of CVE-2023-4020 in the wild and no public exploit code.

## Other vulnerabilities in silabs.com GSDK

- [CVE-2023-45318](https://insights.sbomify.com/CVE-2023-45318/): Memory corruption in Gecko Platform (critical 10.0)
- [CVE-2023-2686](https://insights.sbomify.com/CVE-2023-2686/): Memory corruption in Gecko Platform (critical 9.8)
- [CVE-2023-4280](https://insights.sbomify.com/CVE-2023-4280/): Unvalidated input in Silicon Labs TrustZone implementation leads to accessing Trusted memory region (critical 9.3)
- [CVE-2023-25181](https://insights.sbomify.com/CVE-2023-25181/): Memory corruption in Cesium NET (critical 9.0)
- [CVE-2023-27882](https://insights.sbomify.com/CVE-2023-27882/): Memory corruption in Cesium NET (critical 9.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-4020 and fix it if it is affected.

What it is: CVE-2023-4020 is a critical memory corruption vulnerability in silabs.com GSDK, published on 15 Dec 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-2023-4020 in the wild and no public exploit code.

Affected product: silabs.com GSDK. 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-2023-4020/ (Markdown: https://insights.sbomify.com/CVE-2023-4020/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-4020
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-4020
- OSV: https://osv.dev/vulnerability/CVE-2023-4020

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-4020/
Summaries are generated and may contain mistakes; the official description above is the record.