# CVE-2020-8125: Improper Input Validation in klona

> Prototype pollution in the klona npm library allows attackers to achieve remote code execution or cause denial of service in applications using the package.

- **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:** 4 Feb 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-8f89-2fwj-5v5r

## What is CVE-2020-8125?

CVE-2020-8125 is a critical code injection vulnerability in klona npm module, published on 4 Feb 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Flaw in input validation in npm package klona version 1.1.0 and earlier may allow prototype pollution attack that may result in remote code execution or denial of service of applications using klona.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2020-8125?

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


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `klona` | npm | All versions | 1.1.1 |
| `klona` | npm | All versions | 1.1.1 |

Products: Klona Project Klona.

## How do I fix CVE-2020-8125?

Upgrade klona to 1.1.1 or later.

## Is CVE-2020-8125 being exploited?

There is no known exploitation of CVE-2020-8125 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-8125 and fix it if it is affected.

What it is: CVE-2020-8125 is a critical code injection vulnerability in klona npm module, published on 4 Feb 2020. 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-2020-8125 in the wild and no public exploit code.

Affected packages and fixed versions:
- klona (npm): affected all versions; fixed in 1.1.1
- klona (npm): affected all versions; fixed in 1.1.1

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-2020-8125/ (Markdown: https://insights.sbomify.com/CVE-2020-8125/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-8125
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-8125
- OSV: https://osv.dev/vulnerability/CVE-2020-8125

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-8125/
Summaries are generated and may contain mistakes; the official description above is the record.