Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) Affecting crypto-js package, versions >=3.1.2-4 <4.0.0
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applicationsSnyk Learn
Learn about Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) vulnerabilities in an interactive lesson.
Start learning- Snyk IDSNYK-JS-CRYPTOJS-18599395
- published9 Aug 2026
- disclosed7 Aug 2026
- creditjuli
Introduced: 7 Aug 2026
NewCVE-2026-71851 (opens in a new tab)How to fix?
Upgrade crypto-js to version 4.0.0 or higher.
Overview
crypto-js is a library of crypto standards.
Affected versions of this package are vulnerable to Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) in the WordArray.random function. An attacker can recover security-sensitive values by enumerating the reduced output space of the underlying pseudo-random number generator. This is only exploitable if the application uses the affected function to generate security-sensitive values.