Ransomware has been on the rise in recent months, and the extent of its ascension might horrify even the most casual observer. The  software, which takes over a computer and effectively holds it—and its contents—hostage until conditions are met usually in the form of a ransom payment, has made some people a lot of money in a very short time. How much? The FBI puts it at around $18 million over the course of just 15 months.

The report—issued in the form of an advisory from the FBI's Internet Crime Complaint Center—spelled it out clearly; more than $1 million a month, on average, was shelled out just to recover a computer from the depths of ransomware's grip. But what's perhaps even more interesting here is that there's been a particular spike in ransomware just over the last two months, according to senior incident response analyst Lance Mueller, who serves with IBM's Emergency Response Services team. Mueller went so far as to note that, while previous months might see 10 to 12 calls for the entire month relating to ransomware, in the last 60 days, that number increased three-fold, making 10 to 12 calls the average for a week.

Perhaps the biggest such ransomware instance is CryptoWall, which generated 992 complaints at the FBI's Internet Crime Complaint Center between April 2014 and June 2015. IBM, meanwhile, is seeing plenty of CryptoWall, but reports suggest that AlphaCrypt and TeslaCrypt are also making inroads on users' systems.

As for how the ransomware reaches the users, it's an insidious process involving a rapidly increasing number of file types. Infected Word documents are just one method; advertising, email, or even websites can be infected with ransomware, and as soon as the infected material is accessed, the horror begins, and the system falls prey to encryption. The key is held by the hostages, who then demand payment—often between $200 and $10,000—and often in Bitcoin. Those who have been hit with ransomware are advised to reach out to the local FBI field office, a list of which can be found online, in a bid to try and stop this practice.

There are some fairly simple ways to protect against ransomware; the obvious, of course, are the old standards: keep up with antivirus programs and don't open unfamiliar attachments. These days, the use of attachments can be circumvented. Text can be put directly into the body of an email. There's also the option of keeping backups of all your files in an offline storage system. Whether it's a portable drive, a thumb drive, or an entirely separate computer, keeping files in more than one place improves the chances of surviving ransomware. It's next to impossible to hack a computer that never goes online—it can be done but it requires a lot of effort to break the so-called “air gap” involved—so keeping files elsewhere better ensures protection.

Ransomware, no matter what form it takes, is dangerous stuff, but protecting against it can be comparatively simple. This hopefully comes as welcome, and instructive news for those concerned about having a system's contents ransomed.