Prototype Pollution Vulnerability in y18n Package

nodejs Updated 02 Oct 2025

Summary

17/11/2020
N/A
Yes i
Critical
9.8

CVE-2020-7774: The package y18n before 3.2.2, 4.0.1 and 5.0.5, is vulnerable to Prototype Pollution. Affects nodejs versions < 10.24.1-r0. Fixed in 10.24.1-r0. How to fix ↓

Free scan

Check if this vulnerability affects your application

Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.

Check my app free

No signup required · Results in about 60 seconds

Upload your dependency manifest or SBOM

Drag & drop your file here or

Java Javascript PHP Python Go Rust Ruby Dart C/C++ Elixir CycloneDX SPDX

Upload a supported dependency manifest or SBOM. No installation or source-code access required.

See supported files and SBOM formats
SBOM sbom.json · bom.json · bom.xml · *.spdx.json · *.cdx.json · *.cdx.xml
Java pom.xml · gradle.lockfile · buildscript-gradle.lockfile
Javascript package-lock.json · yarn.lock · pnpm-lock.yaml
PHP composer.lock
Python poetry.lock · requirements.txt · Pipfile.lock
Go go.mod
Rust Cargo.lock
Ruby Gemfile.lock
Dart pubspec.lock
C/C++ conan.lock
Elixir mix.lock
Enter your work email to receive your report link.

Verify your email to view the full report and start 30 days of continuous monitoring. No credit card required.

Sponsored Devnack Mobile apps built by Devnack Design, build and launch iOS and Android apps with a senior product team. From idea to store release Start a project

Background

The y18n package is a localization library for Node.js applications. It provides a simple way to manage and translate messages in different languages. However, versions before 3.2.2, 4.0.1, and 5.0.5 of y18n are vulnerable to Prototype Pollution.

Vulnerability Detail

Prototype Pollution is a vulnerability that occurs when an attacker can modify the prototype of an object. In the case of y18n, an attacker can manipulate the prototype of the y18n.__n function, leading to potential code execution or denial of service attacks. This vulnerability can be exploited by passing specially crafted language files to the y18n library.

How To Fix

Minimum fixed version

10.24.1-r0

This is the first release that contains the fix.

sudo apk add --upgrade nodejs

Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →

Workaround

Currently, there is no known workaround for this vulnerability. It is crucial to update the y18n package to the fixed versions as soon as possible.

Conclusion

The y18n package is vulnerable to Prototype Pollution, which can lead to code execution or denial of service attacks. It is crucial to update the package to versions 3.2.2, 4.0.1, or 5.0.5 to mitigate this vulnerability. For further support on vulnerability remediation, please contact DevNack.com.

See every vulnerability recorded for nodejs →

Share this vulnerability

FAQ

Prototype Pollution is a vulnerability that allows an attacker to modify the prototype of an object, leading to unexpected behavior or code execution.

The y18n package can be exploited by passing specially crafted language files to the library, which can manipulate the prototype of the y18n.__n function.

This vulnerability can lead to code execution or denial of service attacks, depending on how it is exploited.

No, only versions before 3.2.2, 4.0.1, and 5.0.5 of y18n are vulnerable to this issue.

You can update the y18n package by running the command npm install y18n@latest.

Related vulnerabilities

Recent vulnerabilities recorded for nodejs.

How To Fix

Minimum fixed version

10.24.1-r0

This is the first release that contains the fix.

sudo apk add --upgrade nodejs

Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →

Subscribe to Vulert on Telegram
Daily digest of new CVEs, critical and high severity, affected packages and fixes — plus a weekly roundup.
Join the channel →
Help improve this record
Report an issue or send feedback