Would-be cybercriminals who lack the technological prowess to actually hack into their targets computers themselves can now overcome that hurdle, thanks to a new “ransomware-as-a-service” tool discovered on the darknet by researchers at McAfee.

Branded as “Tox”, the tool lets anyone, regardless of technical ability, automatically create ransomware: software which encrypts a victim’s hard drive and demands payment before decrypting it.

The most notorious example of ransomware, named Cryptolocker, ran wild in the first half of 2014. It demanded a ransom paid in the cryptocurrency bitcoin, rising as high as 2 bitcoin ($2000 at the time), or the victim’s documents were lost forever. In November 2013, a US police force fell prey to the scam and ended up having to pay a ransom equal to £832 at the day’s exchange rates.

But Cryptolocker was disrupted in a simultaneous US-EU raid in June 2014, seizing the command and control network which had been used to run the software remotely. After the raids, which also took out a related piece of malware called Gameover Zeus, reports of new infections have died off.

Tox threatens to revive the problem. But unlike Cryptolocker, which had the hallmarks of a co-ordinated criminal operation, Tox lets would-be criminals roll their own ransomware. Any user can register on the darknet site and choose to create their own cryptolocker-style software. They get the option to set the ransom amount, in US dollars, as well as add a personal note.

The site then automatically generates a downloadable virus, which can be downloaded and then shared however the attacker desires. And the whole thing is funded by Tox taking a 20% cut of any ransom paid.

“We don’t expect Tox to be the last malware to embrace this model. We also anticipate more skilled development and variations in encryption and evasion techniques,” writes McAfee’s Jim Walter.

Tox shows how the hidden side of the tech industry follows the same trends as the surface side. The trend of “software-as-a-service” – charging on a regular basis for programmes, rather than one fee upfront – has grown to the point that Microsoft’s next version of Windows – Windows 10 – will be sold in that way.

Popular enterprise software such as Microsoft Office or Adobe Creative Suite have been sold as services for some time now. What other trends from the enterprise will virus writers follow in the future?