# CVE-2021-3839: Memory corruption in dpdk

> An out-of-bounds memory access flaw in the DPDK vhost library allows attackers to cause a denial of service via crash.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 23 Aug 2022
- **Updated:** 3 Aug 2024
- **Also known as:** DEBIAN-CVE-2021-3839, GHSA-c4mq-4x72-rfxj, UBUNTU-CVE-2021-3839

## What is CVE-2021-3839?

CVE-2021-3839 is a high-severity memory corruption vulnerability in Fedoraproject Fedora, published on 23 Aug 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A flaw was found in the vhost library in DPDK. Function vhost_user_set_inflight_fd() does not validate `msg->payload.inflight.num_queues`, possibly causing out-of-bounds memory read/write. Any software using DPDK vhost library may crash as a result of this vulnerability.

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

## Which versions are affected by CVE-2021-3839?

It affects 4 products.


Products: Dpdk Data Plane Development Kit, Fedoraproject Fedora, Redhat Enterprise Linux, Redhat Enterprise Linux Fast Datapath.

## How do I fix CVE-2021-3839?

Apply the vendor's patch.

## Is CVE-2021-3839 being exploited?

There is no known exploitation of CVE-2021-3839 in the wild and no public exploit code.

## Other vulnerabilities in Fedoraproject Fedora

- [CVE-2020-10725](https://insights.sbomify.com/CVE-2020-10725/): Null dereference in dpdk (high 7.7)
- [CVE-2019-14818](https://insights.sbomify.com/CVE-2019-14818/): Denial of service in dpdk (high 7.5)
- [CVE-2022-0669](https://insights.sbomify.com/CVE-2022-0669/): Denial of service in DPDK (medium 6.5)
- [CVE-2020-10726](https://insights.sbomify.com/CVE-2020-10726/): Denial of service in dpdk (medium 6.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-3839 and fix it if it is affected.

What it is: CVE-2021-3839 is a high-severity memory corruption vulnerability in Fedoraproject Fedora, published on 23 Aug 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-3839 in the wild and no public exploit code.

Affected product: Fedoraproject Fedora. 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-2021-3839/ (Markdown: https://insights.sbomify.com/CVE-2021-3839/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-3839
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-3839
- OSV: https://osv.dev/vulnerability/CVE-2021-3839

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-3839/
Summaries are generated and may contain mistakes; the official description above is the record.