# CVE-2021-3661: Code injection in HP Workstation BIOS

> Attackers can execute arbitrary code on HP Workstations via a vulnerability in the UEFI firmware, requiring firmware updates to mitigate.

- **Severity:** High 8.4 (`CVSS:3.1/AV:L/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 21 Nov 2022
- **Updated:** 29 Apr 2025
- **Also known as:** GHSA-8r2c-p9ww-m55w

## What is CVE-2021-3661?

CVE-2021-3661 is a high-severity code injection vulnerability in HP Workstation BIOS, published on 21 Nov 2022. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A potential security vulnerability has been identified in certain HP Workstation BIOS (UEFI firmware) which may allow arbitrary code execution. HP is releasing firmware mitigations for the potential vulnerability.

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2021-3661?

It affects 20 products.


Products: Hp Z1 All-in-One G3 Firmware, Hp Z238 Microtower Firmware, Hp Z240 Small Form Factor Firmware, Hp Z240 Tower Firmware, Hp Z2 Mini G3 Firmware, Hp Z2 Mini G4 Firmware, Hp Z2 Mini G5 Firmware, Hp Z2 Small Form Factor G4 Firmware, Hp Z2 Small Form Factor G5 Firmware, Hp Z2 Small Form Factor G8 Firmware, Hp Z2 Tower G4 Firmware, Hp Z2 Tower G5 Firmware, Hp Z2 Tower G8 Firmware, Hp Z440 Firmware, Hp Z4 G4 Firmware, Hp Z640 Firmware, Hp Z6 G4 Firmware, Hp Z840 Firmware, Hp Z8 G4 Firmware, Hp Zcentral 4r Firmware.

## How do I fix CVE-2021-3661?

No fix has been published for CVE-2021-3661 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-3661 being exploited?

There is no known exploitation of CVE-2021-3661 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-3661 and fix it if it is affected.

What it is: CVE-2021-3661 is a high-severity code injection vulnerability in HP Workstation BIOS, published on 21 Nov 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-2021-3661 in the wild and no public exploit code.

Affected product: HP Workstation 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-2021-3661/ (Markdown: https://insights.sbomify.com/CVE-2021-3661/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-3661
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-3661
- OSV: https://osv.dev/vulnerability/CVE-2021-3661

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From sbomify Insights: https://insights.sbomify.com/CVE-2021-3661/
Summaries are generated and may contain mistakes; the official description above is the record.