Ethical Hacking News
Five cryptocurrency wallet apps, including RRWallet, Bexo Wallet, NanChat, Bitcoin Libre, and Milo, have been found vulnerable to a CryptoJS Weak RNG that exposed users to $5.7 million in drains. Coinspect has identified the vulnerability and advised affected users to update their wallets for security patches.
CryptoJS Weak RNG affects five cryptocurrency wallet apps, causing a total theft of $5.7 million. The vulnerability was introduced 12 years ago and is due to the use of weak entropy in recovery phrase generation. Users whose wallets have been affected should check for updates or seek guidance from official channels to prevent further losses. The vulnerability highlights the importance of ensuring all software and applications are up-to-date with latest security patches.
CryptoJS Weak RNG Behind $5.7 Million in Drains Affects Five Crypto Wallet Apps
In a recent revelation, Coinspect has identified a Cryptographic JavaScript Library (CryptoJS) weakness that is impacting five different cryptocurrency wallet applications. This vulnerability, which was introduced 12 years ago, affects the generation of recovery phrases for these wallets. The firm's on-chain analysis puts the total theft at a lower bound of roughly $5.7 million.
The blockchain security firm, Coinspect, has been analyzing the wallets and discovered that the CryptoJS library, specifically its WordArray.random() function, supplied weak entropy that led to the drains in some applications. To put this into perspective, the expected search space for a 128-bit or 256-bit entropy would be 2^128 or 2^256, respectively. However, due to the weakness, these search spaces were reduced to roughly 2^39 and 2^47, making it possible to enumerate on ordinary hardware.
Coinspect analyzed the wallets that used this weak random number generator for recovery-phrase generation, including RRWallet, Bexo Wallet, NanChat, Bitcoin Libre, and Milo. The firm reported that five applications are affected by this vulnerability. Although some of these applications have been fixed in newer versions, it is essential for users to check the current version and migration guidance on the projects' official channels.
The library's weak code was introduced as part of a cryptographic randomness generator called Multiply-With-Carry, which arrived in June 2014. This function seeded its randomness from Math.random(). However, later releases restored this weakness due to a change being considered breaking at the time. An upgrade within 3.x could therefore move a project from a fixed release to a vulnerable one.
Coinspect identified ferrumnet/bip39 as a React Native fork that replaced upstream bip39's native cryptographic randomness with CryptoJS. This indicates that there were alternative routes into wallet software using this weak random number generator.
CryptoJS maintainer Evan Vosberg published GHSA-rg76-677x-56q9, which had a Critical rating and CVSS score of 9.0. It lists every release below 4.0.0, despite the exceptions mentioned earlier. Coinspect confirmed that an application is affected only if it uses this function to generate security-sensitive values.
Once a recovery phrase has been generated from the vulnerable function's output, subsequent hashing or PBKDF2 processing cannot restore the missing entropy. If the user had previously created a wallet with the vulnerable version, they need to create a new securely generated recovery phrase and move their funds immediately.
The vulnerability was exploited in two drain waves: May 27 sweep took about $3.14 million from 431 accounts, while the second run between May 30 and July 13 took $2.55 million from addresses tied to 522 seeds. Coinspect tracked 2,114 identified seeds and associated addresses across Bitcoin, Ethereum, Tron, Rootstock, and Polygon. The total losses come out to $5,690,922 through July 13.
Coinspect advised users whose wallets have been affected to check the current version of their application for updates that include a fix or seek guidance from the project's official channels for further instructions.
The vulnerability highlights the importance of ensuring that all software and applications are up-to-date with the latest security patches. It also emphasizes the need for vigilance in identifying vulnerabilities and updating wallet applications promptly to prevent such losses.
Related Information:
https://www.ethicalhackingnews.com/articles/CryptoJS-Vulnerability-Exposed-Five-Crypto-Wallet-Apps-Affected-by-Weak-Random-Number-Generator-ehn.shtml
https://thehackernews.com/2026/08/cryptojs-weak-rng-behind-57-million-in.html
Published: Thu Aug 6 07:54:37 2026 by llama3.2 3B Q4_K_M
