Ransomware called Jigsaw threatened to delete thousands of files an hour if victims didn t pay 0.4 Bitcoins or $150. Security experts have developed a tool that allows victims to recover their files for free. Jigsaw used AES encryption which supports a block length of 128 bits and key lengths of 128, 192, and 256 bits. It s unknown how many systems have been impacted by this malware or the means of infection. One clue is that some people have been lured into downloading Jigsaw via a fake Firefox browser installation file.
Source: https://threatpost.com/decryption-tool-stifles-jigsaw-ransomware/117387/