Michael Yoder and Suraj Acharya remind us that Hadoop clusters are made up of computers on a network, which means people will try to install malicious software:
Roughly two years ago there were a spate of attacks against the open source database solution MongoDB, as well as Hadoop. These attacks were ransomware: the attacker wiped or encrypted data and then demanded money to restore that data. Just like the recent attacks, the only Hadoop clusters affected were those that were directly connected to the internet and had no security features enabled. Cloudera published a blog post about this threat in January 2017. That blog post laid out how to ensure that your Hadoop cluster is not directly connected to the internet and encouraged the reader to enable Cloudera’s security and governance features.
That blog post has renewed relevance today with the advent of XBash and DemonBot.
The origin story of XBash and DemonBot illustrates how security researchers view the Hadoop ecosystem and the lifecycle of a vulnerability. Back in 2016 at the Hack.lu conference in Luxembourg, two security researchers gave a talk entitled Hadoop Safari: Hunting for Vulnerabilities. They described Hadoop and its security model and then suggested some “attacks” against clusters that had no security features enabled. These attacks are akin to breaking in to a house while the front door is wide open.
Their advice is simple, but simple is good here: it means you should be able to implement the advice without much trouble.