Rensenware’s warning screen asks for a high score, rather than the usual pay off, to decrypt your files.
At this point, Ars readers have heard countless tales of computer users being forced to pay significant sums to unlock files encrypted with malicious ransomware. So we were a bit surprised when word started to trickle out about a new bit of ransomware that doesn’t ask for money. Instead, “Rensenware” forces players to get a high score in a difficult PC shoot-em-up to decrypt their files.
As Malware Hunter Team noted yesterday, users on systems infected with Rensenware are faced with the usual ransomware-style warning that “your precious data like documents, musics, pictures, and some kinda project files” have been “encrypted with highly strong encryption algorithm.” The only way to break the encryption lock, according to the warning, is to “score 0.2 billion in LUNATIC level” on TH12 ~ Undefined Fantastic Object. That’s easier said than done, as this gameplay video of the “bullet hell” style Japanese shooter shows.
Gameplay from TH12 ~ Undefined Fantastic Object on Lunatic difficulty. Players needed to get 200 million points to unlock the “Rensenware” malware.
As you may have guessed from the specifics here, the Rensenware bug was created more in the spirit of fun than maliciousness. After Rensenware was publicized on Twitter, its creator, who goes by Tvple Eraser on Twitter and often posts in Korean, released an apology for releasing what he admitted was “a kind of highly-fatal malware.”