# CVE-2022-21190: Prototype Pollution

> Prototype pollution in convict allows attackers to modify object prototypes, potentially leading to code execution or privilege escalation.

- **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:** 13 May 2022
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-jjf5-wx3j-3fv7, SNYK-JS-CONVICT-2774757

## What is CVE-2022-21190?

CVE-2022-21190 is a high-severity vulnerability in convict, published on 13 May 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

This affects the package convict before 6.2.3. This is a bypass of [CVE-2022-22143](https://security.snyk.io/vuln/SNYK-JS-CONVICT-2340604). The [fix](https://github.com/mozilla/node-convict/commit/3b86be087d8f14681a9c889d45da7fe3ad9cd880) introduced, relies on the startsWith method and does not prevent the vulnerability: before splitting the path, it checks if it starts with __proto__ or this.constructor.prototype. To bypass this check it's possible to prepend the dangerous paths with any string value followed by a dot, like for example foo.__proto__ or foo.this.constructor.prototype.

Weakness: CWE-1321 (Improperly Controlled Modification of Object Prototype Attributes)

## Which versions are affected by CVE-2022-21190?

2 open source packages ship an affected version, including convict. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `convict` | npm | All versions | 6.2.3 |
| `convict` | npm | All versions | 6.2.3 |

Products: Mozilla Convict.

## How do I fix CVE-2022-21190?

Upgrade convict to 6.2.3 or later.

## Is CVE-2022-21190 being exploited?

There is no known exploitation of CVE-2022-21190 in the wild and no public exploit code.

## Other vulnerabilities in convict

- [CVE-2023-0163](https://insights.sbomify.com/CVE-2023-0163/): Prototype Pollution in convict (high 8.4)
- [CVE-2022-22143](https://insights.sbomify.com/CVE-2022-22143/): Prototype Pollution (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-21190 and fix it if it is affected.

What it is: CVE-2022-21190 is a high-severity vulnerability in convict, published on 13 May 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-2022-21190 in the wild and no public exploit code.

Affected packages and fixed versions:
- convict (npm): affected all versions; fixed in 6.2.3
- convict (npm): affected all versions; fixed in 6.2.3

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-2022-21190/ (Markdown: https://insights.sbomify.com/CVE-2022-21190/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-21190
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-21190
- OSV: https://osv.dev/vulnerability/CVE-2022-21190

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-21190/
Summaries are generated and may contain mistakes; the official description above is the record.