# CVE-2021-46894: Use after free in EMUI

> A use-after-free flaw in the uinput module allows attackers to achieve kernel privilege escalation on Huawei devices.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/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:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 6 Jul 2023
- **Updated:** 19 Nov 2024
- **Also known as:** GHSA-w232-x2q6-cvwm

## What is CVE-2021-46894?

CVE-2021-46894 is a critical use after free vulnerability in Huawei Emui, published on 6 Jul 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Use After Free (UAF) vulnerability in the uinput module.Successful exploitation of this vulnerability may lead to kernel privilege escalation.

Weakness: CWE-416 (Use After Free), CWE-269 (Improper Privilege Management)

## Which versions are affected by CVE-2021-46894?

It affects 2 products.


Products: Huawei Emui, Huawei Harmonyos.

## How do I fix CVE-2021-46894?

No fix has been published for CVE-2021-46894 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-46894 being exploited?

There is no known exploitation of CVE-2021-46894 in the wild and no public exploit code.

## Other vulnerabilities in Huawei Emui

- [CVE-2023-52370](https://insights.sbomify.com/CVE-2023-52370/): Memory corruption in EMUI (critical 9.8)
- [CVE-2023-52378](https://insights.sbomify.com/CVE-2023-52378/): Business logic in EMUI (critical 9.8)
- [CVE-2023-52381](https://insights.sbomify.com/CVE-2023-52381/): Code injection in EMUI (critical 9.8)
- [CVE-2023-52103](https://insights.sbomify.com/CVE-2023-52103/): Memory corruption in EMUI (critical 9.8)
- [CVE-2023-46773](https://insights.sbomify.com/CVE-2023-46773/): Privilege escalation in EMUI (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-46894 and fix it if it is affected.

What it is: CVE-2021-46894 is a critical use after free vulnerability in Huawei Emui, published on 6 Jul 2023. 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-2021-46894 in the wild and no public exploit code.

Affected product: Huawei Emui. 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-2021-46894/ (Markdown: https://insights.sbomify.com/CVE-2021-46894/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-46894
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-46894
- OSV: https://osv.dev/vulnerability/CVE-2021-46894

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-46894/
Summaries are generated and may contain mistakes; the official description above is the record.