Knight Ransomware Group's Attack on the City of Defiance

Knight ransomware group claimed an attack against the City of Defiance. The group obtained 390GB of sensitive data, including employee records, law enforcement videos, emails, and various confidential documents, including contracts. Defiance is a city in and the county seat of Defiance County, Ohio, United States, about 55 miles (89 km) southwest of Toledo and 47 miles (76 km) northeast of Fort Wayne, Indiana, in Ohio's northwestern corner.

Knight Ransomware Emergence

Knight ransomware first came to attention in July when the group overhauled the interface and code of the Cyclops ransomware. As part of their operation, they continue to recruit affiliates through the RAMP hacking forum to enhance their ability to steal data from both Windows and Linux systems. In addition to their regular encryptors, the Knight ransomware operation offers a 'lite' version suitable for spam, spray-and-pray, and batch distribution campaigns.

Deceptive Recruitment Tactics

The Knight ransomware gang employs an HTML attachment labeled 'TripAdvisor-Complaint-[random].PDF.htm,' which redirects users to a deceptive web browser interface impersonating TripAdvisor. Within this simulated browser window, users are prompted to review a restaurant complaint, but it is, in fact, a ruse. When users click on the 'Read Complaint' button, an Excel file titled 'TripAdvisor_Complaint-Possible-Suspension.xll' is downloaded onto their system. This download subsequently triggers the activation of ransomware.

Ransomware Encryption and Demands

The Knight Lite ransomware encryptor, injected into a new explorer.exe process, is utilized to encrypt files on targeted computers. Following encryption, the encrypted files' names are appended with the '.knight_1' extension, where '1' indicates the lite version. Subsequently, the ransomware generates a ransom note in each folder on the compromised computer, demanding a payment of $5,000 to be sent to a provided Bitcoin address.