A hacker or hackers sneaked a backdoor into a widely used open source code library with the aim of surreptitiously stealing funds stored in bitcoin wallets. The malicious code was inserted in two stages into event-stream, a code library with 2 million downloads that’s used by Fortune 500 companies and small startups alike.
In stage one, version 3.3.6, published on September 8, included a benign module known as flatmap-stream. Stage two was implemented on October 5 when flatmap-steam was updated to include malicious code that attempted to steal bitcoin wallets and transfer their balances to a server located in Kuala Lumpur. The backdoor came to light last Tuesday with this report from Github user Ayrton Sparling.