The hackers behind the notorious Shade ransomware have shut down their operations and released over 750,000 decryption keys along with instructions to help victims decrypt their data.
The group, also known as Troldesh or Encoder.858 had been active since 2014, mostly targeting users in Russia and Ukraine. In a message left on a Github repository, the group revealed that it had stopped targeting victims since the end of 2019, however they did not reveal the reasons for shutting down.
The hackers have published the decryption keys along with their decryption software aiming that antivirus companies can create better tools to help users decrypt their data. Kaspersky has already verified the keys and announced that it is creating a free decryption tool.
As well as apologizing to all their victims, the Github post of the operators of the ransomware suggests that they have deleted all the source codes.
“We are the team which created a trojan-encryptor mostly known as Shade, Troldesh or Encoder.858. In fact, we stopped its distribution in the end of 2019. Now we made a decision to put the last point in this story and to publish all the decryption keys we have (over 750 thousands at all),” the post read
“We are also publishing our decryption soft; we also hope that, having the keys, antivirus companies will issue their own more user-friendly decryption tools. All other data related to our activity (including the source codes of the trojan) was irrevocably destroyed. We apologize to all the victims of the trojan and hope that the keys we published will help them to recover their data,” it added.
Experts suggest that Shade ransomware was one of the oldest and most active ransomware strains in existence. While hackers used a combination of email scam and exploit kits to distribute it, it was not considered as perfect since antivirus tools, including Kaspersky and McAfee, were successful in decrypting some systems.
It is likely that these keys are valid for all the versions of Shade ransomware and may be valid for all the users who were impacted. While the security researchers may come up with an easy tool to decrypt data, there may be very few users who have still stored their encrypted data as people generally wipe the infected devices to install fresh operating systems.