# CVE-2021-21555: Memory corruption in PowerEdge BIOS Intel 15G

> A heap-based buffer overflow in Dell PowerEdge BIOS allows local high-privilege attackers to execute arbitrary code, cause denial of service, or disclose information.

- **Severity:** Medium 6.1 (`CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 14 Jun 2021
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-pcxr-3rxm-vvmx

## What is CVE-2021-21555?

CVE-2021-21555 is a medium-severity memory corruption vulnerability in Dell PowerEdge BIOS Intel 15G, published on 14 Jun 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

Dell PowerEdge R640, R740, R740XD, R840, R940, R940xa, MX740c, MX840c, and T640 Server BIOS contain a heap-based buffer overflow vulnerability in systems with NVDIMM-N installed. A local malicious user with high privileges may potentially exploit this vulnerability, leading to a denial of Service, arbitrary code execution, or information disclosure in UEFI or BIOS Preboot Environment.

Weakness: CWE-787 (Out-of-bounds Write), CWE-122 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2021-21555?

It affects 9 products.


Products: Dell Poweredge Mx740c Firmware, Dell Poweredge Mx840c Firmware, Dell Poweredge R640 Firmware, Dell Poweredge R740 Firmware, Dell Poweredge R740xd Firmware, Dell Poweredge R840 Firmware, Dell Poweredge R940 Firmware, Dell Poweredge R940xa Firmware, Dell Poweredge T640 Firmware.

## How do I fix CVE-2021-21555?

No fix has been published for CVE-2021-21555 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-21555 being exploited?

There is no known exploitation of CVE-2021-21555 in the wild and no public exploit code.

## Other vulnerabilities in Dell PowerEdge BIOS Intel 15G

- [CVE-2021-21554](https://insights.sbomify.com/CVE-2021-21554/): Memory corruption in PowerEdge BIOS Intel 15G (medium 6.1)
- [CVE-2021-21556](https://insights.sbomify.com/CVE-2021-21556/): Memory corruption in PowerEdge BIOS Intel 15G (medium 6.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-21555 and fix it if it is affected.

What it is: CVE-2021-21555 is a medium-severity memory corruption vulnerability in Dell PowerEdge BIOS Intel 15G, published on 14 Jun 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-21555 in the wild and no public exploit code.

Affected product: Dell PowerEdge BIOS Intel 15G. 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-2021-21555/ (Markdown: https://insights.sbomify.com/CVE-2021-21555/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-21555
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-21555
- OSV: https://osv.dev/vulnerability/CVE-2021-21555

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From sbomify Insights: https://insights.sbomify.com/CVE-2021-21555/
Summaries are generated and may contain mistakes; the official description above is the record.