# CVE-2021-26334: AMD Chipset Driver Information Disclosure Vulnerability

> A vulnerability in the AMD μProf driver allows lower-privileged users to access kernel MSRs, leading to privilege escalation and ring-0 code execution.

- **Severity:** Critical 9.9 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Dec 2021
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-4xjc-qqh2-pgwj

## What is CVE-2021-26334?

CVE-2021-26334 is a critical vulnerability in AMD μProf Tool, published on 1 Dec 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

The AMDPowerProfiler.sys driver of AMD μProf tool may allow lower privileged users to access MSRs in kernel which may lead to privilege escalation and ring-0 code execution by the lower privileged user.

Weakness: CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2021-26334?

It affects 1 product.


Products: Amd Amd Uprof.

## How do I fix CVE-2021-26334?

No fix has been published for CVE-2021-26334 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-26334 being exploited?

There is no known exploitation of CVE-2021-26334 in the wild and no public exploit code.

## Other vulnerabilities in AMD μProf Tool

- [CVE-2023-20562](https://insights.sbomify.com/CVE-2023-20562/): Untitled advisory (high 7.8)
- [CVE-2022-23831](https://insights.sbomify.com/CVE-2022-23831/): Denial of service in AMD μProf (high 7.5)
- [CVE-2022-27674](https://insights.sbomify.com/CVE-2022-27674/): Denial of service in AMD μProf (high 7.5)
- [CVE-2023-20556](https://insights.sbomify.com/CVE-2023-20556/): Untitled advisory (medium 5.5)
- [CVE-2023-20561](https://insights.sbomify.com/CVE-2023-20561/): Untitled advisory (medium 5.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-26334 and fix it if it is affected.

What it is: CVE-2021-26334 is a critical vulnerability in AMD μProf Tool, published on 1 Dec 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-26334 in the wild and no public exploit code.

Affected product: AMD μProf Tool. 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-2021-26334/ (Markdown: https://insights.sbomify.com/CVE-2021-26334/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-26334
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-26334
- OSV: https://osv.dev/vulnerability/CVE-2021-26334

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-26334/
Summaries are generated and may contain mistakes; the official description above is the record.