# CVE-2021-21551: Dell dbutil Driver Insufficient Access Control

> A local attacker can exploit insufficient access control in the Dell dbutil driver to escalate privileges, cause denial of service, or disclose information.

- **Severity:** High 8.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Yes, since 31 Mar 2022 (CISA KEV)
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 4 May 2021
- **Updated:** 21 Oct 2025
- **Also known as:** GHSA-pp2j-9hqv-7x55

## What is CVE-2021-21551?

CVE-2021-21551 is a high-severity vulnerability in Dell dbutil, published on 4 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Dell dbutil_2_3.sys driver contains an insufficient access control vulnerability which may lead to escalation of privileges, denial of service, or information disclosure. Local authenticated user access is required.

Weakness: CWE-782 (Exposed IOCTL with Insufficient Access Control)

## Which versions are affected by CVE-2021-21551?

It affects 1 product.


Products: Dell Dbutil.

## How do I fix CVE-2021-21551?

No fix has been published for CVE-2021-21551 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 21 Apr 2022.

## Is CVE-2021-21551 being exploited?

Yes. Attackers have exploited CVE-2021-21551 in the wild since at least 31 Mar 2022.

Public exploit code:

- Exploit to SYSTEM for CVE-2021-21551 (github_poc): https://github.com/waldo-irc/CVE-2021-21551
- Cobalt Strike (CS) Beacon Object File (BOF) foundation for kernel exploitation using CVE-2021-21551. (github_poc): https://github.com/tijme/kernel-mii
- arbitrary kernel read/write in dbutil_2_3.sys, Proof of Concept Local Privilege Escalation to nt authority/system (github_poc): https://github.com/mathisvickie/CVE-2021-21551
- Dell Driver EoP (CVE-2021-21551) (github_poc): https://github.com/ihack4falafel/Dell-Driver-EoP-CVE-2021-21551
- Dell Driver EoP (CVE-2021-21551) (github_poc): https://github.com/nanabingies/CVE-2021-21551
- https://github.com/ch3rn0byl/CVE-2021-21551 (github_poc): https://github.com/ch3rn0byl/CVE-2021-21551

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-21551 and fix it if it is affected.

What it is: CVE-2021-21551 is a high-severity vulnerability in Dell dbutil, published on 4 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2021-21551 in the wild since at least 31 Mar 2022.

Affected product: Dell dbutil. 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-2021-21551/ (Markdown: https://insights.sbomify.com/CVE-2021-21551/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-21551
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-21551
- OSV: https://osv.dev/vulnerability/CVE-2021-21551

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-21551/
Summaries are generated and may contain mistakes; the official description above is the record.