# CVE-2021-46461: Memory corruption in n/a

> An out-of-bounds array access in the njs JavaScript engine used by NGINX can lead to memory corruption, potentially allowing code execution or denial of service.

- **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:** Yes
- **Published:** 14 Feb 2022
- **Updated:** 4 Aug 2024
- **Also known as:** ALPINE-CVE-2021-46461, CLEANSTART-2026-PU38791, GHSA-8g5q-f4mq-w57g

## What is CVE-2021-46461?

CVE-2021-46461 is a critical memory corruption vulnerability in n/a, published on 14 Feb 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

njs through 0.7.0, used in NGINX, was discovered to contain an out-of-bounds array access via njs_vmcode_typeof in /src/njs_vmcode.c.

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2021-46461?

It affects 1 product.


Products: Nginx Njs.

## How do I fix CVE-2021-46461?

Upgrade to a fixed version.

## Is CVE-2021-46461 being exploited?

There is no known exploitation of CVE-2021-46461 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2022-35173](https://insights.sbomify.com/CVE-2022-35173/): Memory corruption in n/a (high 7.5)
- [CVE-2022-29779](https://insights.sbomify.com/CVE-2022-29779/): Null dereference in n/a (medium 5.5)
- [CVE-2022-29780](https://insights.sbomify.com/CVE-2022-29780/): Null dereference in n/a (medium 5.5)
- [CVE-2022-30503](https://insights.sbomify.com/CVE-2022-30503/): Null dereference in n/a (medium 5.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-46461 and fix it if it is affected.

What it is: CVE-2021-46461 is a critical memory corruption vulnerability in n/a, published on 14 Feb 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-2021-46461 in the wild and no public exploit code.

Affected product: n/a. 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-2021-46461/ (Markdown: https://insights.sbomify.com/CVE-2021-46461/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-46461
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-46461
- OSV: https://osv.dev/vulnerability/CVE-2021-46461

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-46461/
Summaries are generated and may contain mistakes; the official description above is the record.