Rensenware targets anime fans with crazy decryption challenge

Be careful what you download, anime lovers. A new type of ransomware has been mistakenly released online.

To decrypt your files, Rensenware asks you to play anime-style shooter game Touhou Seirensen and, instead of asking for an outrageous sum of money, it only requires you to reach the insane score of 200 million points (the “lunatic” level) that not even the author of the malware could beat when he infected his own computer.

The developer is a student from Korea under the name Typle Eraser. According to the author who has, since then, released an apology online, Rensenware was developed solely for fun and was not meant to be malicious. The ransomware was posted on GitHub and spread within hours. Following the infection, the student released the decryption software.

“I made it for joke, and just laughing with people who like Touhou Project Series. So I distributed source code except compiled binary on the web,” the apology reads. “However, at the point of the distribution, the tragedy was beginning. A number of people blamed me. It’s natural. because I made accident definitely wrong. I’m not sure this apology is enough to you. If not, then I apologize again… It didn’t meant to be evil. I hope you understand of it. [sic]”

Even though the initial plan was not to cause harm and the source code has been removed, parts of the code are probably online in some archive and, eventually, a hacker will think of altering it to make it incorruptible.