Crypto Market Hit by Decade-Old Bug Exposing Web Wallet Security Flaw

A 12-year-old bug in the CryptoJS JavaScript library has led to a major series of coordinated thefts on the crypto market, exposing a hidden threat at the foundation of popular web and mobile wallets.

The vulnerability, codenamed 'Ill Bloom,' allowed hackers to brute-force users' secret seed phrases using ordinary home computers. This bug was present in CryptoJS library versions 3.x, starting with 3.1.2, except for versions 3.2.0 and 3.2.1.

The situation worsened because the defective random number generation function produced predictable combinations, narrowing seed phrase security down to a limited range of possible variants. CryptoJS was shipped 'under the hood' of hundreds of other software packages, while wallet developers used it blindly for years.

The first wave of mass thefts occurred on May 27, 2026, when 431 accounts were hit in one day, with attackers withdrawing $3.14 million at once. Bitcoin holders took the largest hit, losing $2.57 million, followed by Ethereum ($286,000), Rootstock ($177,000), Tron ($81,000), and Polygon ($23,000).

The list of affected applications has expanded to include RWallet (RRWallet), Bexo Wallet, NanChat, Bitcoin Libre, and Milo Wallet. Some of these wallets have already shut down, leaving users without support.